UGR scientists describe for the first time what is the dynamics that mitochondria follow when we exercise.
This information, unknown to date, has important consequences for sports performance and the prevention of metabolic pathologies
Scientists from the University of Granada (UGR) have discovered for the first time what is the dynamics that mitochondria follow when we practice exercise, information unknown to date and that has important consequences in sports performance and in the prevention of pathologies metabolic.
Mitochondria are the cellular organelles responsible for producing the energy required for eukaryotic cells, essential for the movement of species and for organized life.
In all textbooks, mitochondria commonly appear as oval, static, and little-changing organelles. “However, today we know that they function as a coordinated collective, that they are dynamic and that they are subjected to processes of fusion or fission, which in turn determines their functionality and even susceptibility to promoting metabolic diseases”, explains the professor of the department Physiology of the UGR Jesús Francisco Rodríguez Huertas, main author of this work.
Specifically, cells with a predominance of fissured mitochondria lose functionality and are prone to aging and obesity. While a predominance of fusion, forming long filaments, is associated with greater functionality and a reduction in non-communicable metabolic diseases.
In the study carried out at the UGR, and for the first time in science, the authors have investigated whether mitochondrial fusion / fission processes take place in the muscle mass of athletes during training and maximum efforts.
A double mechanism
“We have shown that mitochondria fuse in muscle in a few minutes and do so transversely to myofibrils. This could explain one of the physiological questions that have been with us for a long time: “Does oxygen really reach the center of the muscle myofibrils during maximal efforts?” Asks the UGR professor.
The answer would be simple: mitochondria, by fusing transversely, would capture oxygen in the sarcoplasmic membrane and release ATP in the center of the myofibrils without the need for oxygen to get there.
In addition, the UGR scientists have shown in this article that this process is due to a double mechanism: a molecular mechanism due to the activation of proteins involved in fusion, and a mechanical mechanism, since the glycogen column, parallel to the myofibrils, it would crush the mitochondria during the contraction phase like soap bubbles.
In any case, this mechanism is reversible, since after three hours of rest the tendency is for mitochondrial fission to recover the classic oval shape of rest, as it appears in textbooks.
Mitochondrial dynamics in muscle biopsies obtained in swimmers at rest, after 60 minutes of high intensity exercise and after three hours of recovery. Mitochondria are surrounded by yellow.
Proposal for a mitochondrial fission mechanism by crushing the glycogen column during the contraction of myofibrils.
The UGR research team that has carried out this work.
