Nerve-to-muscle signal failure linked to weakness in older adults
A cross-sectional comparison of 10 older adults and eight younger adults found disrupted nerve-to-muscle signaling linked to weakness severity.
Limit: The human comparison included only 10 older adults with physical limitations
Stake: Authors work for NMD Pharma. An author founded Bolden Therapeutics.
Edited by Boris Djordjevic · AgingResearch.News
A cross-sectional study compared 10 adults aged 83–96 who reported physical limitations (40% women) with eight adults aged 20–45 (38% women). Weak older participants had failures at neuromuscular junctions, where nerves activate muscles. Greater signaling failure correlated with more severe weakness. Separate human biopsies showed reduced levels of NaV1.4, a sodium channel that helps muscle fibers become electrically active, at these junctions.
In animal experiments, blocking ClC-1, a chloride channel that restrains muscle activation, improved signaling and muscle function in old rodents. A blinded experiment gave 20-month-old male rats either the ClC-1 inhibitor NMD1226 at 60 milligrams per kilogram twice daily for seven days (five rats), or water (four rats). Grip strength improved during dosing but fell to near control levels one day after dosing stopped.
Why it matters
Sarcopenia, the age-related loss of muscle strength and size, can limit independence. The authors identify nerve-to-muscle signaling as a potential target for addressing this weakness.
Caveats
The small, cross-sectional human comparison cannot establish that signaling failure caused weakness. It involved older adults with reported physical limitations, and drug benefits were tested in rodents, not people.
The paper
University of Missouri; Ohio University
The Journal of Clinical Investigation, Jul 9, 2026, Open access
