A study published in the journal ACS Pharmacology & Translation Science has shown that giving mice long-term, low doses of a key cannabis component can reduce the effects of ageing on the brain.
In the study, researchers treated elderly mice with small daily doses of tetrahydrocannabinol (THC) for several weeks. The ageing mice showed improved learning, memory, and cognitive ability while their brains started producing new connections between neurons, a process typically associated with younger, developing brains.
Researchers from University Hospital Bonn and the Hebrew University of Jerusalem gave 18-month-old mice, equivalent to about 65 in human years, low doses of THC via implanted pumps for 28 days. They then conducted various tests to assess the mice’s cognitive abilities and examined their brains and other tissues.
The treatment improved cognitive performance in the older mice and increased the formation of new connections between neurons in their brains. It also caused widespread changes in metabolism, particularly in the brain and fat tissue. When the same treatment was given to younger mice for comparison, similar cognitive improvements were not seen.
Researchers believe that THC activates a specific protein switch in the brain called mTOR (Mechanistic Target of Rapamycin). Giving ageing mice THC led to an increase in mTOR activity, boosting energy production and the formation of synaptic proteins, thereby improving cognition.
“We concluded that long-term THC treatment initially has a cognition-enhancing effect by increasing energy and synaptic protein production in the brain, followed by an anti-ageing effect by decreasing mTOR activity and metabolic processes in the periphery,” said Dr Andras Bilkei-Gorzo from the Institute of Molecular Psychiatry at the University Hospital Bonn. “Our study suggests that a dual effect on mTOR activity and the metabolome could be the basis for an effective anti-ageing and cognition-enhancing drug.”
While this study was limited due to only being conducted on mice, other research has shown a positive correlation between cannabis and cognitive function in humans. A study published earlier in 2024 found that people who consume cannabis have a lower chance of experiencing subjective cognitive decline (SCD) compared to people who do not. A cohort of 4744 adults aged 45 and above had their frequency of cannabis use, method and reason for consuming it examined against reported instances of SCD. The results of the study showed a 96% lower chance of experiencing SCD in those who used cannabis recreationally when compared to those who did not use cannabis at all.
