Jokes abound related to how people tend to forget more as they age: “Why did I walk into this room?” “I know I’ve read this book before, but I forgot what happens, so it’s like reading a new book.” If the results of a recently reported study on mice from the University of Bonn are borne out, cannabis may help cut the jokes, to say nothing of improving the quality of life of millions of older people.
The researchers found that altering mice genes to stop the mammalian endocannabinoid system from working properly causes the mice to age faster and display a greater decline in cognitive function. A properly functioning mammalian endocannabinoid system balances a human body’s reaction to stress. The psychoactive component of marijuana, THC, mimics the molecules of that system.
The observed effect is exactly the opposite of the observed effect of marijuana on young mice (and people). Teenagers who use marijuana perform less well on memory and attention tasks while under the influence of THC, but low doses of the substance may have the opposite effect in older people, according to a report in New Scientist.
Here’s a description of the research:
[T]he team gave young (2-month-old), middle-aged (12-month-old) and elderly (18-month-old) mice a steady dose of THC. The amount they received was too small to give them psychoactive effects.
After a month, the team tested the mice’s ability to perform cognitive tasks, such as finding their way around mazes, or recognising other individuals.
In the control groups, which received no THC, the young mice performed far better than the middle-aged and elderly mice. But the middle-aged and elderly mice who had been given THC performed as well as the young mice in the control group.
Further studies showed that THC boosted the number of connections between brain cells in the hippocampus, which is involved in memory formation.
The German researchers are planning to conduct human trials using purified THC in precisely controlled doses to find out if older people experience the same beneficial effects as older mice, and if they do, at what age.
But even if it does work the same way in people, lead researcher Andreas Zimmer told New Scientist that it is unlikely that doctors will prescribe weed for their patients: “Smoking marijuana is very different.”