New research suggests Alzheimer's disease might show early warning signs in a surprising place: outside the brain. Scientists have found that genetic mutations linked to Alzheimer's can mess with the nerves controlling muscle movement, even without brain or spinal cord involvement. This could explain why some people experience changes in walking or coordination long before memory problems kick in.
Researchers at the University of Central Florida (UCF) used advanced lab systems made from human cells to explore how inherited Alzheimer's mutations impact movement. Their findings, published in Alzheimer's & Dementia: The Journal of the Alzheimer's Association, indicate that motor deficits might signal the disease earlier, potentially allowing for interventions before central nervous system symptoms appear.
While Alzheimer's is typically known for memory loss and cognitive decline, doctors have noted physical symptoms like balance and gait changes appearing years before clear cognitive issues. This study focused on familial Alzheimer's, a rarer, inherited form, to see if movement problems stem solely from brain damage or if Alzheimer's can directly affect nerves elsewhere.
Using a "human-on-a-chip" technology, scientists created a miniature model of the connection between nerve and muscle cells, deliberately excluding the brain and spinal cord. They found that motor neurons carrying familial Alzheimer's mutations disrupted normal nerve-to-muscle communication, suggesting movement issues could originate in the peripheral nervous system, not just the brain.
This discovery could pave the way for earlier detection of Alzheimer's by looking at motor function alongside cognitive symptoms. It also raises questions about treatment, as therapies focused solely on the brain might miss issues affecting peripheral nerves and muscles. The innovative lab technology used in the study shows promise for researching various diseases and treatments by better mimicking human physiology.
