Enzyme That may Contribute to Schizophrenia, Psychiatric Disorders Identified

A new study on mice has found that the lack of an enzyme that contributes to Alzheimer's disease can result in the development of a number of schizophrenia-like behaviours.

Neuroscientists at Johns Hopkins say that the finding raises the possibility that this enzyme may participate in the development of schizophrenia and related psychiatric disorders and therefore may provide a new target for developing therapies.

The BACE1 enzyme, for beta-site amyloid precursor protein cleaving enzyme, generates the amyloid proteins that lead to Alzheimer's disease.

The research team years ago suspected that removing BACE1 might prevent Alzheimer.

"We knew at the time that in addition to amyloid precursor protein, BACE1 interacts with other proteins but we didn't know how those interactions might affect behavior," says Alena Savonenko, M.D., Ph.D., an assistant professor in neuropathology at Hopkins.

They describe how mice lacking the BACE1 enzyme show deficits in social recognition among other behaviours classically linked to schizophrenia.

A normal mouse, when introduced to another mouse, shows a lot of interest the first time they meet. If the mice are separated then reintroduced, their interest drops because they remember having met before, a phenomenon the researchers call habituation. If they then introduce a completely different mouse, interest piques again at the newbie.

The researchers introduced mice lacking BACE1 to another mouse. The first time they met, the BACE1 mouse showed interest, the second time meeting the same mouse the BACE1 mouse showed less interest and even less interest the third time. The researchers then introduced the BACE1 mouse to a totally different mouse of a different strain and the BACE1 mouse showed no interest at all.