Researchers in the United States have discovered that the defects in the muscle maturation process of Huntington's disease (HD) mice may explain some of the symptoms of HD. The title of this study was published in the online journal "Journal of General Physiology" on November 29, 2016. "Progressive Cl? Channel disorder reveals impaired skeletal muscle maturation in R6/2 Huntington's disease mice.
This study believes that HD is both a neurodegenerative disease and a muscle tissue disease, so skeletal muscle treatment may improve the patient's motor function. HD is a progressive disease caused by mutations in the Huntington gene and is ultimately a fatal disease. This mutation can cause defects in the huntingtin RNA and protein molecules, thereby disrupting the metabolic processes of various cells. HD-related cognitive and mental disorders, such as memory loss and mood swings, are thought to be the result of the death of nerve cells in the striatum and cerebral cortex. However, certain motor symptoms of the disease, such as involuntary movement and muscle stiffness, may be caused by the action of mutant huntingtin in skeletal muscle. VAndrewVoss and colleagues previously found that mice with early-onset HD showed skeletal muscle defects in the later stages of the disease, especially the decreased function of a protein called ClC-1. I'm. The ions are guided inside the battery. This may be due to poor processing of the messenger RNA encoding ClC-1, which leads to increased muscle excitability and may lead to certain motor symptoms related to HD. However, the loss of ClC-1 function may only be a slow response to neuronal death that stimulates skeletal muscle.
Research In this new study, Voss and colleagues at White State University (Dayton, Ohio) and California State Institute of Technology (Pomona, California) studied the entire disease process in HD model mice. When HD mice and control mice were young, they misprocessed the RNA encoding ClC-1, but when they grew up, only healthy animals could properly process the RNA to produce functional ClC-1. Will be able to do it. Therefore, compared with healthy control animals, the ClC-1 function of the skeletal muscle of HD mice is reduced even before motor symptoms begin to appear.
This shows that HD mice can interfere with muscle maturation. Voss and colleagues found that HD mice express myosin, a muscle motor protein that is normally only produced in the muscles of newborn mice. In addition, they found similar defects in the muscle maturation of different strains of adult HD mice. In the skeletal muscle fibers of mice with early-onset Huntington's disease, the RNA (red) encoding mutant huntingtin protein forms lesions in the nucleus (blue).
"Our findings support that HD is not only a neurodegenerative disease, but also a muscle disease, providing new opportunities to target skeletal muscle tissue to improve patient care. We may provide it," Voss said. In addition, researchers and clinicians may be able to use skeletal muscle defects as biomarkers to track the development of HD. This is much easier than examining the patient’s brain tissue.