University of Missouri researchers identify cause of age-related muscle weakness

Researchers at the University of Missouri have identified a previously overlooked cause of age-related muscle weakness. According to a study published in the Journal of Clinical Investigation, the decline in muscle strength in older age is not solely due to the loss of muscle mass or motor neurons, but rather a decrease in communication reliability at the neuromuscular junction.

Specifically, the levels of the sodium channel protein NaV1.4 decrease significantly with age, making muscles less responsive to nerve impulses. However, a research team led by W. David Arnold found that this failure may be reversible. By partially blocking the ClC-1 chloride channel, scientists were able to restore the electrochemical balance in the muscle membrane. In animal trials, this intervention made aged muscles more sensitive to nerve impulses and significantly increased muscle strength.