DNA Damage Linked To Alzheimer’s

Not only does amyloid-β, the hallmark biomolecule associated with Alzheimer’s disease, trigger an inflammatory response in the brain when it aggregates, it probably also increases nerve cell DNA damage, according to a report (Nat. Neurosci., DOI: 10.1038/nn.3356). Commenting on the study, Peter J. McKinnon, a geneticist at St. Jude Children’s Research Hospital, in Memphis, says it provides “new insights into how the Alzheimer’s-related factor may lead to cell loss and neurodegeneration associated with the disease.” A team led by Lennart Mucke of the University of California, San Francisco, measured breaks in the nerve cell DNA of normal mice and of mice engineered to produce human amyloid-β. The team found that the engineered mice had up to four times as many nerve cells containing damaged DNA in their brains as did normal mice. When the team gave the antiepilepsy drug levetiracetam to amyloid-positive mice for a month, levels of DNA damage in nerve cells decreased to those found in nonengineered mice. According to Mucke, amyloid-β seems to increase DNA damage by provoking abnormal nerve activity, something that FDA-approved levetiracetam suppresses.