The study suggests a possible role in preventing the disease before it starts developing. Blood flow to parts of the brain can drop years before memory problems appear in people who carry APOE4, a gene variant associated with a higher risk of Alzheimer’s disease. That change offers a possible early warning, but researchers still need to determine whether intervening during those symptom-free years can help prevent the disease from developing.
Professor in the University of Missouri’s School of Medicine, Ai-Ling Lin investigated that possibility using rapamycin, a drug being studied for its antiaging effects. Healthy adults ages 45 to 65, including people with and without APOE4, took a low dose daily for four weeks. None had developed symptoms of Alzheimer’s disease, and only those carrying the variant showed improved blood flow in the brain. “We also found that females with APOE4 saw the greatest improvement in brain blood flow, which is significant given that nearly two-thirds of people with Alzheimer’s are women. “This research is an example of precision medicine, as we work to identify who can benefit from this drug the most,” Lin said.
Rapamycin slowed brain aging in mice Lin had begun exploring rapamycin before coming to Missouri, looking beyond its usual roles in preventing organ transplant rejection and treating certain rare diseases. In mice with APOE4, she found that it could slow brain aging as well as improve cerebral blood flow. Those findings prompted her to investigate whether the benefits would extend to middle-aged people carrying the same variant. Improved blood flow in these healthy adults suggests a possible role for rapamycin in preserving cognitive function, although the four-week study does not establish whether it will protect memory or prevent Alzheimer’s later in life. “Alzheimer’s tends to happen more in older people, especially for those with APOE4.
