Recently, a study published in the journal Nature Communications described the daily exercise as an important element to help the cells of the muscular system of the human body to stay healthy and strong.
This research provides scientists with a more accurate understanding of the processes at the cellular level, and how exercise can improve muscle health. In addition, it is possible to reduce the risk of death in human populations through daily exercise.
“Whether the muscle is healthy or not really determines whether the whole body is healthy or not,” says lead investigator Professor Zhen Yan of the University of Virginia School of Medicine in Charlottesville. “And exercise capacity, determined primarily by muscle size and function,” he adds, “is the best predictor of mortality in the general population.”
According to the new study, muscle health could be improved by the renewal of its cellular nerve center: mitochondria. These are crucial structures for the proper functioning of the human body. They can also determine our overall health and longevity.
Mitochondria have the ability to convert the food we eat into energy. Mitochondria transform proteins, fats and sugars into fuel that the body needs to work on a daily basis.
So, exercise can act on mitochondria in muscles?
The new study has described many factors and processes in mitochondria through “mitophagy”. Mitophage, describes the process by which damaged or defective mitochondria are selected and removed, usually after a period of stress.
When we talk about muscles, the mito- phago could help keep healthy human skeletal muscle. And the best way to show how exercise induces this process, Prof. Yan and his colleagues have genetically modified a group of mice to carry a gene that helps inform about the effects of physical activity.
This gene is called pMitoTimer. It causes a strange effect, but necessary in this type of studies. It makes the mitochondria can be fluorescent, allowing researchers to study the mitophagy process in vivo, having placed the laboratory rodents to run on tape for 90 minutes.
After 12 hours of the experiment, researchers observed that mitochondria showed signs of stress. After 6 hours, they saw signs of mitophage. Prof. Yan has explained the effect of daily exercise on mitochondria through an analogy that could explain this process by eliminating the defective cells of the muscle.
“Aerobic exercise eliminates damaged mitochondria in skeletal muscle, if it does repeatedly, continues to eliminate the damaged ones, has a better muscle with better mitochondrial quality, clean the clunkers, now the city, the cell, is full of health, functional cars “said Prof. Zhen Yan
Chemical reaction in identified mito- phage
The researchers also identified the molecular mechanism behind the process. the scientists placed the genetically modified mice in a training inside the treadmill seemed to activate a kinase called AMPK.
A kinase is an enzyme that modifies other proteins through a process called phosphorylation. In this biochemical process, phosphate groups are added to proteins. The researchers determined that a biochemical chain reaction occurs, and AMPK triggers another kinase called Ulk1.
Prof. Yan stated about this process saying: “When it is turned on, Ulk1 activates other components in the cell to perform the elimination of dysfunctional mitochondria.” “It’s analogous to a 911 call where a trailer removes the clunkers.” However, “we still do not know how these activities are coordinated”.
However, the scientists should confirm their discovery, and prove that Ulk1 plays an essential role in mitophagy. In this way the team of researchers created mouse model that lacks the Ulk1 gene. These mice were also subjected to exercise on the treadmill, but the resulting mito- phage was significantly inhibited.