Muscle wasting can sometimes be life-threatening, and so far treatment options are very limited. Scientists at the Biozentrum of the University of Basel have now developed two protein building blocks that can be used to treat a specific hereditary form of muscle weakness. In the animal model, muscle wastage with the designed proteins was successfully stopped.
"People who suffer from muscle atrophy often lack essential building blocks in the cell scaffold," explain the scientists. The cytoskeleton, which holds the muscle fibers together and protects them from damage, can not perform its function, the muscles become weak and increasingly weaker. The research team led by Professor Markus Rüegg from the Biozentrum of the University of Basel has now succeeded in stabilizing the cytoskeleton with two protein modules designed to restore muscle strength and strength. The scientists published their study results in the journal "Science Translational Medicine".
Congenital muscular dystrophy, a severe form of muscle atrophy
According to the researchers, the term muscle atrophy is used to summarize various muscle diseases that are triggered by defective hereditary factors. The so-called congenital muscular dystrophy is a rare but very severe form of muscle wasting. The disease occurs immediately after birth or in infancy and those affected are also referred to as "flabby children" because their muscles have no tension and are powerless, explains the first author of the study, Judith Reinhard. With age, the disease gets worse as the muscles continuously degrade. Affected children often never learn to walk independently and the respiratory muscles are affected, the expert continues.
No drugs available for therapy
To date, there are no medications that can stop the progression of congenital muscular dystrophy. Life expectancy is therefore very low and many sufferers die before reaching adulthood, the researchers report. The specific form of muscle weakness is based on a genetic defect in the so-called laminin α2.This central component of the outer cytoskeleton connects the latter with the inner part of the muscle fibers and thus ensures the cohesion of the tissue. In the case of gene defects in laminin-α2, according to the scientists, the muscles are extremely unstable and even normal stress leads to inflammation, damage and finally to the breakdown of the muscle fibers.
Designated Proteins Successfully Tested
According to the researchers, another laminin called laminin-α4 is in its place in people who can not produce laminin α2.However, this complicates the tasks much worse, because it is not very well built into the cytoskeleton. With the newly developed proteins, however, the scientists have succeeded in the animal model to improve the muscle power and body weight of the diseased animals and significantly extend their lifespan. The two proteins contribute to laminin-α4 binding and anchoring better to the muscle cell as well as to each other, explain the experts.
Almost normal life expectancy achieved
"In animals with a laminin α2 defect, muscle tension and strength as well as body weight improved markedly," reports Professor Rüegg. The connectors have been used to stabilize the muscle fibers."We were particularly pleased to see that the animals treated with the linker proteins have an almost normal life expectancy," emphasizes the study leader. Some animals have even become older than their healthy siblings."The two designed linker proteins could possibly be used in the future gene therapy for the treatment of congenital muscular dystrophy," the conclusion of Prof. Rüegg.(fp)