New Study Shows THC Reverses Aging
Marijuana has a potential new medical use in the treatment of dementia and the reversal of brain aging if results of a preliminary animal study pan out. Low doses of THC reverses aging, or at least the cognitive signs of aging in mice, according to a study published May, 2017 in the journal Nature Medicine.
Researchers at the University of Bonn in Germany and The Hebrew University of Jerusalem conducted a study administering low doses of THC to mice as old as 12 and 18 months (which is quite old in mouse years). The THC allowed the old mice to perform as well on cognitive tests as 2-month-old mice.
As we age, cognitive decline tends to make it more difficult to learn new things and to multi-task. In extreme cases, this degradation leads to dementia. Reversing or prolonging that process, or at least the signs of it, would extend an individual’s quality of life.
THC And The Endocannabinoid System
Just as our muscles do, our endocannabinoid system loses tone as we age– giving credence to the adage that “our brain is a muscle”. The endocannabinoid system is a group of receptors on neuronal membranes that fit together like a lock and key with naturally-produced neurotransmitter chemicals called endocannabinoids. These transmitters travel through the spaces between nerve cells, locking into the receptors.
This initiates a reaction to affect production of other neurotransmitters that affect mood, appetite, pain, perception and a host of other functions of the nervous and endocrine systems. Because of this, a neuroscientist writing in the journal Cerebrum called endocannabinoids the “traffic cops” of the nervous system.
Endocannabinoid “tone” refers to the efficiency level at which your endocannabinoid system is functioning. As we age, our body doesn’t produce or degrade endocannabinoids as well, and some of those endocannabinoid receptors on neurons quit functioning.
Scientists have observed the loss of endocannabinoid tone and age-related cognitive decline in tandem, but the animal study published in May is the first time researchers have documented a link between the two.
THC And The Hippocampus
It turns out, according to the study, sustained low doses of THC increased the density of receptors in the hippocampus, a part of the brain crucial for forming new memories and certain autonomic functions. Increased receptor density in the hippocampus is usually seen after learning. One could speculate that the mice performed better on the tests because their hippocampi were equipped to learn more easily.
“The researchers administered a small quantity of THC, the active ingredient in the cannabis plant, to mice aged two, 12 and 18 months over a period of four weeks,” reports MedicalXpress.com. “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.”
Restoration of CB1 signaling in old individuals could be an effective strategy to treat age-related cognitive impairments
However, other studies have shown that chronic high doses of THC can actually shrink the hippocampus. More research is needed to ascertain the right dosage for medical benefits.
Also, researches noted the level of THC administered were so low it did not cause the psychoactive effects marijuana is famous for when used recreationally.
The next step? Human trials, though none have yet been advertised publicly as of May 2017.