THC is being meticulously researched, and more and more scientific evidence is accumulating, suggesting the compound could have medical uses. A new piece of evidence, which has recently been reported by German and Hebrew scientists, shows that pure THC could help halt or even reverse age-related cognitive impairment, at least in rodents.
A team of researchers from the University of Bonn (Germany) and Hebrew University (Israel) conducted a study, in which they looked at mice of different ages and their reaction to low THC doses. The aim was to determine what effect THC produces on rodents’ cognitive function.
The system on which the research was focused is the endocannabinoid system. While we do not know much about it, as many mechanics of it remain a mystery, the scientists hypothesized that it is this system that influences age-related cognitive impairment. As a person ages, endocannabinoid levels fall, which brings certain changes in the brain. That is why the researchers thought that stimulating the endocannabinoid system activity by administering THC could counteract the effects of the decline.
It has been known for quite a long time that younger mice have better memory and learn more efficiently. However, when a young mouse brain is exposed to THC, performance is not that good. In this study, two groups of mice were used: in one of them, there were only young mice, while the other one included old mice.
Each group was divided into two subgroups: some rodents received a dose of THC for 28 consecutive days (long enough to be considered chronic THC exposure), while others were not given the compound. When the experiment was over, the scientists assessed the mice’s learning capabilities and memory. As of the day of assessment, there was no THC in their blood.
The researchers reported that the performance of old mice with THC record was similar to that of young mice that did not receive the chemical. Not only did intake of THC correlate with cognitive function improvement, but they also revealed significant changes in the brain: in old mice that received the chemical, there were more neuron connections in the hippocampus. Genomic changes also followed: while lifespan- and plasticity-related genes appeared to be turned up, those that drive cognitive impairment were less active.
The researchers modified genes in several mice to see what changes in the receptors follow, if THC is administered regularly. As a body ages, the number of CB1 receptors, which are used by the endocannabinoid system, decreases, and THC seems to activate the remaining CB1 receptors, thus trying to compensate for their activity and number decline.
Much left to be studied
The research findings are promising, but there are a number of problems that remain unresolved and prevent the scientists from translating them to humans.
- First, organisms of a human and of mice are different, and so are their metabolisms. Even if the mechanism works in mice, it does not mean the phenomenon can be seen in humans.
- Second, the researchers used pure THC, which is not tolerated that well, compared to edible cannabis or its smoking version.
- Third, the dose that could produce the same effect in humans is not the same as the one that fits mice, because rodents are less sensitive to such substances.
Still, the researchers believe THC can help reverse age-related cognitive impairment, and are conducting another study – this time, in humans. Please do not resort to smoking cannabis just because of these preliminary findings: they are limited, the approach has not been trialed yet, and consumption of cannabis can lead to a range of diseases.