Nearly half of people over 80 develop sarcopenia — the age-related loss of muscle mass and function. Researchers at the University of Missouri have found that the cause is not only the breakdown of muscle itself or the death of neurons: a failure in the signaling between nerves and muscles plays a key role, infohub.kz reports.
A team led by D. David Arnold, executive director of the NextGen Precision Health initiative, found that the reliability of the nerve-muscle connection declines substantially with age. According to the researchers, it is this breakdown in communication that drives the development of sarcopenia.
Loss of strength was previously attributed to the destruction of muscle tissue or the death of neurons. The new findings, however, point to a different cause — disrupted communication at the neuromuscular junction. The researchers linked this failure to lower levels of the protein NaV1.4, which helps muscle fibers respond to signals from the nervous system. Animal experiments and observations in humans confirmed that this mechanism breaks down as the body ages.
Working with the Danish biotechnology company NMD Pharma, the scientists were able to partially block another protein, ClC-1. This made aging muscles more sensitive to nerve impulses and increased their strength in animal models. A similar approach previously showed positive results in trials of the experimental drug ignaseclant in patients with Charcot-Marie-Tooth disease.
According to the authors, the method could form the basis of a treatment for sarcopenia in older adults.