13 Oct 1998

Secreted forms of amyloid precursor protein (APP) may play an important role in the formation and consolidation of memory, according to a study published in today's proceedings of the National Academy of Science. Researchers from the Universite Louis Pasteur in Strasbourg, France, and Lilly Research Laboratories found that secreted forms of APP greatly enhance memory in mice when injected into their cerebrospinal fluid during a variety of tasks involving short-term or long-term memory. The doses of APP were very low and assumed to reflect normal levels in the body. Control experiments showed that the injections did not alter the animals' motor performance or exploratory activity, suggesting that the effects are specific to memory formation. APP is a large molecule from which derive smaller fragments called beta amyloid peptide, which accumulate in the brains of Alzheimer's patients and are thought to be toxic to brain cells. Mutations in APP can cause an inherited form of Alzheimer's disease. It is interesting to speculate whether alterations in APP levels or function may play a role in the pathogenesis of Alzheimer's disease.—June Kinoshita