New drug raises hopes of reversing memory loss in old age

Toronto researchers believe the drug can also help those with depression, schizophrenia and Alzheimer’s

An experimental drug that bolsters ailing brain cells has raised hopes of a treatment for memory loss, poor decision making and other mental impairments that often strike in old age.

The drug could be taken as a daily pill by over-55s if clinical trials, which are expected to start within two years, show that the medicine is safe and effective at preventing memory lapses.

Tests in the lab showed that old animals had far better memory skills half an hour after receiving the drug. After two months on the treatment, brain cells which had shrunk in the animals had grown back, scientists found.

Etienne Sibille, at the Centre for Addiction and Mental Health in Toronto, said the treatment was aimed not only at the “normal” cognitive decline that leads to senior moments, but at memory loss and mental impairments that commonly afflict people with depression, schizophrenia and Alzheimer’s disease.

If the drug did well in human trials, Sibille said it was possible that “anybody over the age of 55-60 who may be at risk of cognitive problems later on could benefit from this treatment”.

“Our findings have direct implications for poor cognition in normal ageing,” he said, with the drug potentially improving learning, memory, decision making and essential life planning. “But we see this deficiency across disorders from depression to schizophrenia and Alzheimer’s.”

There are no medicines on the market that improve the sort of memory loss seen in old age and psychiatric disorders such as depression and schizophrenia. But the Toronto researchers believe their drug can reverse failing memories by targeting specific cells involved in learning and memory, and rejuvenating them. The changes the drug brings about in the brain suggest it could prevent memory loss at the beginning of Alzheimer’s and potentially delay its onset.

Research on memory loss has shown that it is partly linked to levels of a neurotransmitter known as GABA. Its normal job is to slow down the rate at which neurons fire, effectively dampening down electrical “noise” in the brain. Lower this background noise and important signals in the brain can be processed more easily, or so the theory goes.

The new drug is a derivative of benzodiazepine, a family of medicines that includes the anti-anxiety pills Valium and Xanax. While Valium and Xanax have broad effects in the brain, the new drug is designed to target specific GABA “receptors” found on neurons in key parts of the brain, such as the hippocampus, which are heavily involved in cognition.

Scientists tested the drug on mice in a maze and found that half an hour after receiving a single dose, old animals performed nearly as well as young mice. The drug also restored the performance of young mice whose memories had been temporarily impaired by the stress of being kept in a confined space.

“An old mouse will naturally perform at about 50-60% on this test. Its working memory is basically not working. But within 30 minutes of administration of the drug, their performance is back up to 80-90%, so almost at the level of a young mouse. We have a rapid reversal of age-related working memory deficit and that is exciting,” Sibille told the Guardian.

In the latest work, the Toronto team showed that brain cells which had shrunk in older mice grew back after two months of having the drug put in their drinking water. “We can actually grow the brain cells,” Sibille said.

“They tend to shrink with age and they shrink in neurodegenerative diseases. What we see is that the cells grow to a level that’s pretty close to that in young animals.”

The lab tests showed no benefit when the drug was given to healthy young animals, suggesting that it would not work like a cognitive enhancer and give healthy people superhuman memory skills. “It’s not a drug a student would take if they wanted to be smarter when they study for their exams,” Sibille said. The researchers submitted a patent on the drug on Wednesday before a talk at the American Association for the Advancement of Science annual meeting in Washington DC.

Scientists now hope to test the drug in humans, with the first trials expected to be in people with depression. When people are in remission from depression, those with poor memory and other mental impairments are often most likely to relapse, Sibille said.

“If we could somehow treat those deficits we could potentially have a major impact on the lifelong trajectory of the illness in those people. It would be a gamechanger in how we treat depression.”

Contributor

Ian Sample Science editor

The GuardianTramp

Related Content

Article image
Scientists reverse memory decline using electrical pulses
Working memory of older group temporarily improves to match younger group in study

Hannah Devlin Science correspondent

08, Apr, 2019 @3:00 PM

Article image
Umbilical cord blood could slow brain's ageing, study suggests
Scientists hope protein infusion which rejuvenated brains of aged mice could combat mental decline in older people

Ian Sample Science editor

19, Apr, 2017 @5:02 PM

Article image
Sleep 'resets' brain connections crucial for memory and learning, study reveals
Discovery that sleeplessness causes neurons to become ‘muddled’ with electrical activity could help develop new treatments for mental health disorders

Ian Sample Science editor

23, Aug, 2016 @3:22 PM

Article image
Alzheimer's link to herpes virus in brain, say scientists
Research reveals strains of virus more abundant in brains with early stage of disease, though uncertain whether virus is a trigger or a symptom

Hannah Devlin Science correspondent

21, Jun, 2018 @3:00 PM

Article image
The drugs do work: antidepressants are effective, study shows
Doctors hope study will put to rest doubts about the medicine, and help to address global under-treatment of depression

Sarah Boseley Health editor

21, Feb, 2018 @11:30 PM

Article image
Six lifestyle choices to slow memory decline named in 10-year study
Over-60s who combined more healthy lifestyle choices enjoyed most benefit, found Beijing researchers

Andrew Gregory Health editor

25, Jan, 2023 @11:30 PM

Article image
Drug for hyperactivity may help reverse memory decline in ageing brains

A drug that lowers levels of a chemical called cAMP could improve working memory, a study in monkeys suggests

Anna Perman

29, Jul, 2011 @3:33 PM

Article image
Alzheimer's treatment within reach after successful drug trial
Tablet that ‘switches off’ production of toxic amyloid proteins could be first treatment licensed in a decade if it is also shown to slow mental decline

Hannah Devlin Science correspondent

02, Nov, 2016 @6:00 PM

Article image
Trial shows tantalising signs that new Alzheimer's drug could benefit early-stage patients
Injections of the antibody aducanumab appear to slow condition in patients at earliest stages of disease, raising hopes for treatment

Ian Sample Science editor

31, Aug, 2016 @5:00 PM

Article image
Lifestyle changes could prevent a third of dementia cases, report suggests
Researchers admit prevention estimate is a ‘best-case scenario’, but stress that action can be taken to reduce dementia risk

Nicola Davis

20, Jul, 2017 @4:00 AM