Discovered cellular mechanism in the origin of muscular diseases


It was a group of Portuguese researchers who discovered that a cellular mechanism may be at the origin of diseases or muscle injuries. This discovery may open new avenues for treatments of muscular diseases.

Researchers at the Institute of Molecular Medicine (iMM) have discovered, in an experiment with laboratory mice, the cellular mechanism that may be at the root of diseases or muscle injuries. The news was released this week. The results of the discovery are described in two separate studies, published in Current Biology and Nature Cell Biology journals.

The discovery, said the team of scientists, may open the way to treatments for muscular diseases or injuries caused by intensive sports. Since skeletal muscle (muscle tissue attached to bones) functions normally and contracts, the nucleus of muscle cells is at the periphery of the cell. Thus, in the case of a disease such as dystrophy or myopathy, injury or loss of muscle mass (which occurs with aging), the muscle cell nucleus is at the center of the cell.

Researchers also found that the level of muscle cell nucleus stiffness, which team coordinator Edgar Gomes compared to a ball, conditions the movements and position of that nucleus in the cells. If the ‘ball’ is too soft or hard, the muscle stops working well: this is what happens in case of illness, injury or loss of muscle mass. The “middle term” thus corresponds to the “normal cell situation”, meaning that the muscle is working well, he told Lusa Edgar Gomes.

“If we can control the rigidity of the nucleus with drugs, with treatments, this can correct the positioning of the nucleus and improve the functioning of the muscle”, he said.

By observing the mechanism in muscle tissue produced from rat cells, iMM researchers have also discovered several proteins that activate muscle contraction and cause the muscle cell nucleus to position itself at the periphery. According to Edgar Gomes, these proteins are affected in diseases or muscle injuries.

Their group of researchers is now studying, from such proteins, potential therapeutic targets for muscular diseases such as myopathies.