New drug could reverse memory loss caused by Alzheimer’s disease and depression

Drug returns brain cells to younger state and could help relieve a range of brain problems, scientists say

A new drug has shown promise in reversing memory loss of older people, including those in the early stages of Alzheimer’s disease.

As poor memory can also affect people suffering from mental illness, it may also relieve some of the effects of conditions such as depression.

By homing in on the brain receptors involved in these conditions, the scientists behind the new substance say it is capable of acting “with surgical precision” to revitalise faulty cells.

Though the drug has so far only been used in mice, the team developing it plans to trial it with people suffering depression, and then older patients.

Dr Etienne Sibille of the University of Toronto’s Centre for Addiction and Mental Health, who led the research, said developing medications to deal with these issues was notoriously difficult.

However, he believes the new drug could be administered as a pill to anyone in their late 50s at risk of cognitive problems in old age.

When administered to older or stressed mice, the drug returned them to the condition of far younger individuals.

“Our findings have direct implications for poor cognition in normal ageing. This would include learning and memory, executive functions, decision making and planning,” said Dr Sibille.

The researchers first identified a specific problem with the system controlling the neurotransmitter chemical GABA in the brains of people with depression. The same problem is also found in the brains of those with conditions including schizophrenia and Parkinson’s.

Reactivating this failing system with tweaked versions of the anti-anxiety drugs benzodiazepines turned out to be a powerful way of restoring memory.

Examination of the mice revealed the drugs did not just relieve symptoms but actually modified their brains.

“The aged cells regrew to appear the same as young brain cells,” said Dr Sibille, who was presenting his team’s findings at the American Association for the Advancement of Science meeting in Washington DC.

While the team say they are confident their tests show the molecules enter the brain safely while also producing a marked positive effect, they will not begin applying them in clinical human research for another two years.

Drugs for Alzheimer’s and similar conditions are highly sought after, but trials that succeed in mice do not always produce the same kind of exciting results in humans.

But if the drug is viable, Dr Sibille and his team hope it will also cause fewer of the side effects seen in many existing treatments.