Researchers at an affiliate of a Japanese government-backed research institute said they have discovered that an enzyme in the brain plays a key role in preventing or delaying the development of Alzheimer's disease, the U.S. magazine Science reported Friday.

News of the discovery comes two days after the announcement that a team of researchers led by a Keio University professor has found a gene that prevents brain cells from deteriorating from Alzheimer's.

Alzheimer's, a neurodegenerative disease, kills neuronal cells and shrinks the brain, causing dementia.