What speeds up "biological aging" of the body
Stressful medical procedures, such as surgery or childbirth, can accelerate age-related changes in cells, which then disappear during recovery.In a study published in the journal Cell Metabolism, biologists examined the effects of short-term but extreme physiological stress on the biological age of mice and humans.
They used a so-called DNA methylation clock to quantify epigenetic modifications in DNA structure that are closely linked to aging. DNA methylation refers to the process by which small methyl groups are added to the surface of a DNA molecule and help control how and when certain genes are turned on or off. Evidence suggests that DNA methylation patterns change over the course of life and reflect biological aging.
Scientists first tested the flexibility of biological ageing on mice. They surgically joined pairs of young and old mice so that their blood streams merged for three months, resulting in a significant increase in the biological age of the younger mice. After separating the mice for two months, the researchers found that the increase in age reversed.
The researchers then examined shifts in biological age in people who had undergone major surgery, given birth or received intensive therapy for severe COVID-19 infections. Blood samples from elderly emergency surgery patients showed a spike in biological age within 24 hours of surgery, but their age dropped back to preoperative levels within one to two weeks.
COVID-19 patients who survived infection, however, did not return to normal as quickly. While the women returned to their pre-coronavirus biological age within two weeks, the men did not. This means that the timing of recovery may depend on the type of stress and gender.
In blood samples from pregnant women, researchers found a peak in biological age around the time of birth, which returned to its previous level within an average of six weeks after delivery.
Source: Biological age is increased by stress and restored upon recovery: Cell Metabolism