German and Israeli researchers have found evidence in a new study suggesting that marijuana use may reverse age-related memory loss.
Memory performance and cognitive ability naturally decrease with age, but findings in a new study suggest that cannabis may be able to reverse these aging processes in the brain and potentially help treat dementia.
In the study, recently published in the journal Nature Medicine, researchers from the University of Bonn and The Hebrew University of Jerusalem investigated the effects of four weeks of low-dose treatments of tetrahydrocannabinol (THC) – the psychoactive compound in marijuana — on mice aged two, 12 and 18 months. The mice then underwent a water maze exam and were tested on how quickly they recognized familiar objects to measure their memory performance and learning capacity.
The infusions of THC were shown to make a dramatic impact. The mice that were given a placebo displayed natural age-dependent memory and cognitive loss, while the older mice treated with cannabis showed the same level of cognitive functions as the two-month-old control mice.
“The treatment completely reversed the loss of performance in the old animals,” said Professor Andreas Zimmer, one of the study’s authors.
The cognitive and memory function benefits lasted for weeks, even after the THC infusions ended. No strange side effects were reported.
“These results reveal a profound, long-lasting improvement of cognitive performance resulting from a low dose of THC treatment in mature and old animals,” the study concludes.
The improvement in age-related decline of cognitive abilities suggest that cannabis may be beneficial in efforts to slow the brain aging process and for treating dementia-related conditions like Alzheimer’s disease. The scientists are planning a clinical trial in humans aged 60 to 70 later this year.
“Cannabis preparations and THC are an excellent safety record and do not produce adverse side-effects when administered at a low dose to older individuals. Thus, chronic, low-dose treatment with THC or cannabis extracts could be a potential strategy to slow down or even to reverse cognitive decline in the elderly,” the study reads.
The researchers found that THC’s cognitive benefits were due to its direct interaction with cannabinoid receptor 1 (CB1) of the endocannabinoid system (ECS). The ECS is responsible for regulating several physiological processes, including memory and cognitive function. The study found that THC’s effects were “critically dependent” on the CB1 receptors, as the cognitive improvements didn’t occur when the CB1 receptors were blocked.
The study’s findings suggest that modulating CB1 signaling with cannabis could possibly “be an effective strategy to treat age-related cognitive impairments.” Previous studies investigating cannabis’ effects on dementia have been promising.
“If we can rejuvenate the brain so that everybody gets five to 10 more years without needing extra care then that is more than we could have imagined,” said Andras Bilkei-Gorzo, one of the study’s authors.
You can access the entire study, “A chronic low dose of Δ9-tetrahydrocannabinol (THC) restores cognitive function in old mice,” via Nature Medicine.