MONDAY, Dec. 29, 2003 (HealthDayNews) -- A UCLA neuroscientist says a possible key to the onset of Alzheimer's disease could be the midlife breakdown of myelin, a fatty insulation coating the brain's internal wiring.
Myelin is a sheet of lipid, or fat, containing very high cholesterol content. It serves to speed communication through the brain by wrapping tightly around neural "wire" connections called axons.
Dr. George Bartzokis, a visiting professor of neurology at UCLA, has determined that myelin degrades over time through a combination of genetic factors and the brain's own developmental process. His research involves thorough analysis of magnetic resonance images and post-mortem brain tissue.
"Close analysis of brain tissue and MRIs clearly shows that the brain's wiring develops until middle age and then begins to decline as the breakdown of myelin triggers a destructive domino effect," Bartzokis says. "Our time at the peak is short indeed."
As the brain develops into adulthood, its cholesterol levels grow and eventually promote the production of a toxic protein that attacks the myelin, Bartzokis says. This disrupts message transfer through the axons and eventually leads to the mind-destroying damage visible years later in the cortex of Alzheimer's patients.
Bartzokis suggests preventive therapies worth investigating include medications that lower iron or cholesterol, anti-inflammatory drugs, diet and exercise programs, and hormone replacement therapies.
More information
Here's where you can learn more about Alzheimer's disease.
