Biomarkers of death
Sooner or later death comes for each of us. Researchers at the University of California at Los Angeles, working under the guidance of Professor Steve Horvath, have developed a new tool with which everyone can plan a date with the "angel of death" in advance.
Dubbed "GrimAge" in honor of the "dark Reaper" (from the English Grim Reaper), the complex of DNA methylation biomarkers (DNAmGrimAge) allows predicting the life expectancy and duration of a healthy human life and testing interventions that can potentially slow down or even reverse the process of biological aging.
According to the authors, in terms of predicting life expectancy, GrimAge is 18% more accurate than calendar age and 14% better than the epigenetic biomarkers described earlier. With regard to predicting the age of development of coronary heart disease, these indicators are 61% and 46%, respectively. At the same time, despite this outstanding achievement, it should be borne in mind that neither age nor the assessment of the risk of death using DNAmGrimAge are sufficiently reliable prognostic factors for the development of heart disease.
The DNAmGrimAge biomarker evaluates the risk of human mortality by analyzing the positions of the DNA chain in which age-related methylation changes occur. To analyze the state of these positions, the DNA of blood cells is applied to a chip that evaluates the degree of their methylation in the range from 0 to 1. The results of monitoring more than 1000 such positions are subsequently combined into a predictive value, called GrimAge. If a person falls into the 5% of the most rapidly aging people, the risk of his death is more than 2 times higher than the average value. At the same time, getting into the 5% of the slowest aging people means that the risk of human death is 2 times lower than the average.
GrimAge has such capabilities through the use of methylation provisions that allow tracking blood levels of proteins associated with health status, as well as smoking history. There is strong evidence that smoking history is a good predictor of life expectancy. However, it turned out to be quite unexpected that the method of assessing smoking history based on DNA methylation is even a better predictor of life expectancy than the self-declared smoking history.
The researchers also demonstrated that thin people with fatty liver infiltration and excess visceral fat are epigenetically older than obese people who do not suffer from fatty liver infiltration. However, this is not proof of the safety of obesity, but evidence in favor of the fact that obesity prevention is only one side of the coin. In addition, it is necessary to monitor that adipose tissue does not accumulate in excess, in the "wrong" places and even in places invisible to the eye. It is not surprising that lifestyle factors and diet have once again confirmed their importance, since the use of omega-3 polyunsaturated acids and vegetables are associated with lower GrimAge values. However, in order to recommend omega-3 containing dietary supplements as a rejuvenating agent, this association, identified during the study according to observational data, must be confirmed by the results of a prospective clinical study.
Article Ake T. Lu et al. DNA methylation GrimAge strongly predicts lifespan and healthspan is published in the journal Aging.
Evgenia Ryabtseva, portal "Eternal Youth" http://vechnayamolodost.ru based on EurekAlert materials!: DNA methylation GrimAge strongly predicts lifespan and healthspan.