Physical activity causes many cellular and molecular changes that help improve health — DNOTICIAS.PT

A new study conducted by North American scientists confirms that physical activity causes many cellular and molecular changes in organs that have health benefits.

The health benefits of physical exercise were already well known, but it was still not fully understood how the body changed at the molecular level.

The new research, which was published in the journal Nature, was conducted on mice and 19 organs were studied. The results show that the body's response to prolonged exercise is more complex and comprehensive than previously thought.

According to the authors, prolonged physical activity in these animals caused profound changes in RNA, proteins and metabolites in almost all tissues, providing clues to several human conditions.

To reach these conclusions, the scientists used a series of laboratory techniques to analyze molecular changes in mice that underwent weeks of intense exercise.

Scientists studied different tissues, such as the heart, brain, and lungs, and found that each of the organs changes with exercise, which helps the body regulate the immune system, respond to stress, and control pathways related to inflammatory liver, heart, and tissue diseases.

The investigation was led by MoTrPAC (the Transducers for Physical Activity Consortium), and involved scientists from the Broad Institute – MIT and Harvard University – as well as Stanford University and the US National Institutes of Health.

“This is the first whole-organism map looking at the effects of training on multiple organs. The resources gained will be invaluable and have already yielded many potential new biological insights for further exploration,” emphasized Broad's Steve Carr.

According to Natalie Clark, a computational scientist at Broad University, “There are a variety of different experiences in the same tissue, and this has given a global view of how all these different molecular layers contribute to the response to exercise.”

In total, nearly 10,000 tests were performed, making about 15 million measurements in blood and 18 solid tissues, the Broad Institute explained in a statement.

Scientists found that exercise affects thousands of molecules, with the most extreme changes occurring in the adrenal gland, which produces hormones that regulate many important processes such as immunity, metabolism and blood pressure.

The research made it possible to observe differences according to gender in different organs, especially with regard to the immune response. Most of the women's immune signaling molecules showed changes in their levels between one and two weeks of training, while those in men showed differences between four and eight weeks.

To their surprise, the scientists found an increase in acetylation of mitochondrial proteins, involved in energy production, and a phosphorylation signal that regulates energy storage, both in the liver and in the body, which changes during exercise.

These modifications could help the liver become less fatty and less susceptible to disease through exercise, and could provide a target for future treatments for non-alcoholic fatty liver disease.

“Although the liver is not directly involved in exercise, it undergoes changes that can improve health. No one would have imagined that such changes in acetylcholine and phosphorus would occur after training,” says Jean Beltran, who summarizes: “Exercise is a very complex process.” And this is just the tip of the iceberg.

The authors, who have made the data available to the entire scientific community, hope that their findings will one day be used to tailor exercise to each person's health condition or to develop treatments that mimic the effects of physical activity.