According to the one of the most used proverb “use it or lose it” if one stops using their muscles they will lose their ability through shrinking. However, the recent research states otherwise. They state that this clearly means that the control centers of our body- nuclei are also off-track. A nucleus, an important organelle is responsible for forming new and maintaining muscle fibers.
According to the recent research published in Frontiers in Physiology, modern techniques now have allowed the researchers to observe the nuclei and conclude that nuclei earned during the training are not lost due to muscle cells shrinkage and decomposition.
Researchers have found one of the amazing ways to prevent weakness of muscles in old age that is by banking out muscle growth potential in teenage life through retraining of muscles. Residual myonuclei cause a much faster growth of muscles. This also opens up the fact that athletes who use steroids to grow their muscles may fail in their later life.
Large cells in muscles fuse together
A human body is blessed with a special kind of tissue which looks like a large single cell due to the close compaction of cells. The tissue is known as the syncytium. Lawrence Schwartz, Professor of Biology at the University of Massachusetts said: “Heart, bone and even placenta are built on these networks of cells. But by far our biggest cells—and biggest syncytia—are our muscles.” At first, everything was just confusing with synctia.
He further explained, “Muscle growth is accompanied by the addition of new nuclei from stem cells to help meet the enhanced synthetic demands of larger muscle cells. This led to the assumption that a given nucleus controls a defined volume of cytoplasm—so that when a muscle shrinks or ‘atrophies’ due to disuse or disease, the number of myonuclei decreases.”
Muscle tissues are only capable of gaining Nuclei but not losing it
The myth was believed by many of the researchers as in their studies they noticed that muscle disuse due to inactivity, paralysis or injury, there were signs of nucleus disintegration in muscle atrophy which in actual was cell inflammation. The recent markers and modern dyes have enabled the researchers to overcome this assumption by knowing that there were other cells recruited to atrophic muscle. These recent findings have changed the typical thinking about muscle syncytium.
“Two independent studies—one in rodents and the other in insects—have demonstrated that nuclei are not lost from atrophying muscle fibers, and even remain after muscle death has been initiated.”
As per the study, once the nucleus is formed in the muscle cell, it will stay there forever in the muscle syncytium. Researcher, Schwartz was only found to be unsurprised by the new research. “Muscles get damaged during extreme exercise, and often have to weather changes in food availability and other environmental factors that lead to atrophy. They wouldn’t last very long giving up their nuclei in response to every one of these insults.”
Myonucleus in simple words are the synthetic engine of muscle fibers which means that they should keep in check the muscle size and its strength after an accident to any of these. It ensures better recovery; the phenomenon is known as muscle memory.
“It is well documented in the field of exercise physiology that it is far easier to reacquire a certain level of muscle fitness through exercise than it was to achieve it the first place, even if there has been a long intervening period of detraining. In other words, the phrase “use it or lose it” is might be more accurately articulated as ‘use it or lose it, until you work at it again’.”
Other than understanding muscle biology this new research can help researchers in many fields.
“Informing public health policy, the discovery that myonuclei are retained indefinitely emphasizes the importance of exercise in early life. During adolescence muscle growth is enhanced by hormones, nutrition and a robust pool of stem cells, making it an ideal period for individuals to “bank” myonuclei that could be drawn upon to remain active in old age.”
The research has made the initiative in drug testing for athletes and has banned the cheat steroids which only benefit them long after they quit. “Anabolic steroids produce a permanent increase in users’ capacity for muscle development. In keeping with this, studies show that mice given testosterone acquire new myonuclei that persist long after the steroid use ends.”