A new study led by the researchers at Binghamton University, in collaboration with colleagues at the State University of New York, and Karolinska Institutet and Karolinska University Hospital in Stockholm, described the beneficiary effects of endurance exercise in muscle inflammation (myositis). Endurance exercise helps in managing muscle inflammation.
Myositis is inflammation of the muscles, caused by infection, injury and chronic disease. However, specific forms of myositis such as dermatomyositis and polymyositis result from the autoimmune response, which damages the muscle tissue.
Even though various medications are available for the muscular treatment diseases; they do only half of the job, said Kanneboyina Nagaraju, Professor of Pharmaceutical Sciences at Binghamton University.
Most of the medications target either one immune cell or a group of immune cells, but none of them targets the dying muscles, said Nagaraju. “Yet, exercise takes care of the immune cells that are killing the muscles, and repairs the cell death of the muscle.”
The research team led by Nagaraju made an effort to discover how endurance exercise changes microRNA in skeletal muscles and connect the identified microRNAs with mRNA and protein expressions.
The study involved two groups, one with 12-week endurance exercise, and a non-exercise group. Muscle biopsies were taken before and after undergoing training, to study the effects of exercise. The study found that endurance exercise transformed microRNAs that target and down-regulate immune system.
Endurance exercise also reduced different microRNAs that target and up-regulate mitochondrial content at the protein level. The study findings show that exercise creates microRNA that decreases the number of immune cells and heals the muscle by increasing aerobic metabolism through mitochondrial biogenesis.
The findings were not surprising, said Nagaraju, “The reason why exercise was not considered before is that if people have muscles that are already inflamed or weak, they believed exercise would make the muscles worse. However, what is surprising is the question of why exercise is so effective.
Exercise takes care of the immune cells that are damaging the muscle while simultaneously targeting specific parts of dead or affected muscles.” Even though, there are no drugs available that target the muscle inflammation, endurance exercise and combination of medications may improve the patient’s health and quality of life, concluded Nagaraju.