New research from Washington University School of Medicine in St. Louis has found a close relationship between diabetes and Alzheimer’s disease: Elevated levels of glucose in the blood may raise levels of beta amyloid plaque — thought to be linked to Alzheimer’s — in the brain.
Shannon Macauley, PhD, a postdoctoral researcher, and colleagues made that discovery in mice bred to develop an Alzheimer’s-like condition. In their study, glucose was injected in the bloodstream of the mice.
When glucose levels were doubled in mice without any amyloid plaque, amyloid levels doubled in their brain by 20%, the researchers reported in The Journal of Clinical Investigation. When the experiment was replicated in older mice that already had amyloid buildup, levels of the toxic protein rose by 40%.
It appears that spikes in blood glucose spur neuronal activity in the brain, which promotes beta amyloid production, according to the researchers. The researchers say they are also conducting additional work examining how diabetes medication may be able to impact the way KATP channels on brain cells, which influence the firing of neurons, can potentially treat Alzheimer’s.
“This observation opens up a new avenue of exploration for how Alzheimer's disease develops in the brain as well as offers a new therapeutic target for the treatment of this devastating neurologic disorder,” Macauley said in a statement.
Researchers have uncovered a unique connection between diabetes and Alzheimer’s disease, providing further evidence that a disease that robs people of their memories may be affected by elevated blood sugar, according to scientists at Washington University School of Medicine in St. Louis.
While many earlier studies have pointed to diabetes as a possible contributor to Alzheimer’s, the new study — in mice — shows that elevated glucose in the blood can rapidly increase levels of amyloid beta, a key component of brain plaques in Alzheimer’s patients. The buildup of plaques is thought to be an early driver of the complex set of changes that Alzheimer’s causes in the brain.