Alzheimer's, dementia
© zephr/ SPL
Alzheimer's has been reversed in mice for the first time, raising the hopes of a drug to combat the disease.

Decreasing the levels of a key enzyme - called BACE1 - reduced the levels of amyloid plaques, which are linked to Alzheimer's.

The mice's brains were eventually completely free of these tangles and their cognition improved.

This is the first time scientists have been able to clear the brain of these protein tangles.

It is possible a drug could be developed to help target this enzyme.

Professor Riquiang Yan, who led the study, said:
"To our knowledge, this is the first observation of such a dramatic reversal of amyloid deposition in any study of Alzheimer's disease mouse models."
For the study, the scientists created mice that produce lower levels of the BACE1 protein over time.

The mice were also engineered to develop Alzheimer's.

After developing Alzheimer's at 75 days old, these mice were then clear of the plaques in their brain at 10 months old.

Effectively, one genetic abnormality cured the other.

Their cognition was also improved, although not fully.

Professor Yan said:
"Our study provides genetic evidence that preformed amyloid deposition can be completely reversed after sequential and increased deletion of BACE1 in the adult.

Our data show that BACE1 inhibitors have the potential to treat Alzheimer's disease patients without unwanted toxicity.

Future studies should develop strategies to minimize the synaptic impairments arising from significant inhibition of BACE1 to achieve maximal and optimal benefits for Alzheimer's patients."
The study was published in the Journal of Experimental Medicine (Hu et al., 2018).