Cannabis reverses aging processes in the brain

May 8, 2017
Prof. Dr. Andreas Zimmer (left) and the North Rhine-Westphalia science minister Svenja Schulze (center) are in the lab of the Institute of Molecular Psychiatry at University of Bonn. Credit: © Volker Lannert/Uni Bonn

Memory performance decreases with increasing age. Cannabis can reverse these ageing processes in the brain. This was shown in mice by scientists at the University of Bonn with their colleagues at The Hebrew University of Jerusalem (Israel). Old animals were able to regress to the state of two-month-old mice with a prolonged low-dose treatment with a cannabis active ingredient. This opens up new options, for instance, when it comes to treating dementia. The results are now presented in the journal Nature Medicine.

Like any other organ, our ages. As a result, cognitive ability also decreases with increasing age. This can be noticed, for instance, in that it becomes more difficult to learn new things or devote attention to several things at the same time. This process is normal, but can also promote dementia. Researchers have long been looking for ways to slow down or even reverse this process.

Scientists at the University of Bonn and The Hebrew University of Jerusalem (Israel) have now achieved this in mice. These animals have a relatively short life expectancy in nature and display pronounced cognitive deficits even at twelve months of age. The researchers administered a small quantity of THC, the active ingredient in the hemp plant (cannabis), to mice aged two, twelve and 18 months over a period of four weeks.

Afterwards, they tested learning capacity and memory performance in the animals - including, for instance, orientation skills and the recognition of other mice. Mice who were only given a placebo displayed natural age-dependent learning and memory losses. In contrast, the cognitive functions of the animals treated with cannabis were just as good as the two-month-old control animals. "The treatment completely reversed the loss of performance in the old animals," reported Prof. Andreas Zimmer from the Institute of Molecular Psychiatry at the University of Bonn and member of the Cluster of Excellence ImmunoSensation.

Years of meticulous research

This treatment success is the result of years of meticulous research. First of all, the scientists discovered that the brain ages much faster when mice do not possess any functional receptors for THC. These cannabinoid 1 (CB1) receptors are proteins to which the substances dock and thus trigger a signal chain. CB1 is also the reason for the intoxicating effect of THC in cannabis products, such as hashish or marihuana, which accumulate at the receptor. THC imitates the effect of cannabinoids produced naturally in the body, which fulfil important functions in the brain. "With increasing age, the quantity of the cannabinoids naturally formed in the brain reduces," says Prof. Zimmer. "When the activity of the cannabinoid system declines, we find rapid ageing in the brain."

To discover precisely what effect the THC treatment has in old mice, the researchers examined the brain tissue and gene activity of the treated mice. The findings were surprising: the molecular signature no longer corresponded to that of old animals, but was instead very similar to that of young . The number of links between the nerve cells in the brain also increased again, which is an important prerequisite for learning ability. "It looked as though the THC treatment turned back the molecular clock," says Zimmer.

Next step: clinical trial on humans

A low dose of the administered THC was chosen so that there was no intoxicating effect in the mice. Cannabis products are already permitted as medications, for instance as pain relief. As a next step, the researchers want to conduct a clinical trial to investigate whether THC also reverses ageing processes in the brain in humans and can increase cognitive ability.

The North Rhine-Westphalia science minister Svenja Schulze appeared thrilled by the study: "The promotion of knowledge-led research is indispensable, as it is the breeding ground for all matters relating to application. Although there is a long path from to humans, I feel extremely positive about the prospect that THC could be used to treat dementia, for instance."

Explore further: Bodyguard for the brain: Researchers discover mechanism that can protect from aging processes

More information: Nature Medicine (2017). nature.com/articles/doi:10.1038/nm.4311

Related Stories

Bodyguard for the brain: Researchers discover mechanism that can protect from aging processes

July 12, 2011
Researchers from the Universities of Bonn and Mainz have discovered a mechanism that seems to protect the brain from aging. In experiments with mice, they switched off the cannabinoid-1 receptor. As a consequence, the animals ...

Study links cannabis use in adolescence to schizophrenia

April 26, 2017
Scientists believe that schizophrenia, a disorder caused by an imbalance in the brain's chemical reactions, is triggered by a genetic interaction with environmental factors. A new Tel Aviv University study published in Human ...

Cannabis extract can have dramatic effect on brain cancer, says new research

November 17, 2014
The new research by specialists at St George's, University of London, studied the treatment of brain cancer tumours in the laboratory and discovered that the most effective treatment was to combine active chemical components ...

Study shows memory loss due to cannabis related to harm to mitochondria

November 10, 2016
(Medical Xpress)—An international team of researchers has found what they believe is the source of memory loss in people who smoke marijuana—disruption to mitochondria. In their paper published in the journal Nature, ...

Research finds that ultrasound slows brain ageing

October 12, 2016
Treatment with scanning ultrasound has already been proven to reverse Alzheimer's disease in mice, and now it appears it could also slow down ageing in healthy brains, according to University of Queensland research.

Recommended for you

'Residual echo' of ancient humans in scans may hold clues to mental disorders

July 26, 2017
Researchers at the National Institute of Mental Health (NIMH) have produced the first direct evidence that parts of our brains implicated in mental disorders may be shaped by a "residual echo" from our ancient past. The more ...

Laser used to reawaken lost memories in mice with Alzheimer's disease

July 26, 2017
(Medical Xpress)—A team of researchers at Columbia University has found that applying a laser to the part of a mouse brain used for memory storage caused the mice to recall memories lost due to a mouse version of Alzheimer's ...

Cognitive cross-training enhances learning, study finds

July 25, 2017
Just as athletes cross-train to improve physical skills, those wanting to enhance cognitive skills can benefit from multiple ways of exercising the brain, according to a comprehensive new study from University of Illinois ...

Brain disease seen in most football players in large report

July 25, 2017
Research on 202 former football players found evidence of a brain disease linked to repeated head blows in nearly all of them, from athletes in the National Football League, college and even high school.

Zebrafish study reveals clues to healing spinal cord injuries

July 25, 2017
Fresh insights into how zebrafish repair their nerve connections could hold clues to new therapies for people with spinal cord injuries.

Lutein may counter cognitive aging, study finds

July 25, 2017
Spinach and kale are favorites of those looking to stay physically fit, but they also could keep consumers cognitively fit, according to a new study from University of Illinois researchers.

6 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

cantdrive85
4.3 / 5 (6) May 08, 2017
Must be why I'm still young at heart. ;>)
Victorious D
not rated yet May 09, 2017
This should have been rescheduled forty years ago.

"I feel extremely positive about the prospect that THC could be used to treat dementia, for instance."

Hasn't it already been shown that compounds in cannabis combat the "plaque" that forms during Alzheimer's? Anyway, hooray for research related to cannabis. There's more where that came from.
Anonym
not rated yet May 09, 2017
Now I understand why the people fighting tooth and nail to keep cannabis on Sked 1 exhibit the symptoms of dementia!

RichManJoe
5 / 5 (1) May 09, 2017
Beware, old folks. This sounds like a neat experiment, but then they examine the brain under a microscope.
zorro6204
5 / 5 (2) May 09, 2017
Hey man, I knew pot was making me smarter, because, like . . . um . . . what was I talking about?
BubbaNicholson
1 / 5 (1) May 15, 2017
Cannabis, tea, coffee, brewer's yeast, poppies, even chocolate, these are parasitic species we cultivate and consume for our own compulsion. Sure, they have some medicinal uses, but that is not driving this debate, compulsive consumption is. So, take some genes from poppies and chocolate and call it poppychoc, then give it to your children? I think not.
The reason for the compulsive behavior is addictability and addiction drives human bonding. We need compulsive consumption to keep us in families. Kisses pick up the chemicals from the skin surfaces we kiss. Do you want to replace your son or daughter with poppychoc? I think not.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.