THC could reverse brain aging, according to a recent study

A recent research study has found the fascinating potential of cannabis in the fight against aging, particularly in relation to brain function. This study, conducted by scientists from the University of Bonn, explored the effects of long-term administration of tetrahydrocannabinol (THC) in low doses in mice, revealing surprising results that could pave the way for new approaches to cognitive health.

As we age, our brain becomes slower and less sharp, we become more forgetful, and we find it harder to learn new things. However, the answer to turning back the clock of our aging brain may be hidden in a surprising place: cannabis.

German researchers have found that long-term administration of low doses of a key component in cannabis can reverse the processes of aging in the brain and can have an overall anti-aging effect, according to a new study that could pave the way for new treatments aimed at age-related cognitive impairment.

This research was conducted by teams from University Hospital Bonn (UKB) and the University of Bonn, in collaboration with Israel’s Hebrew University. It was published in the journal ACS Pharmacology & Translation Science, and it focused on the effects of tetrahydrocannabinol (THC) in aged mice and how this influenced key molecular pathways in their brains.

Researchers treated elderly mice with small daily doses of THC for several weeks. The mice showed dramatic improvements in learning, memory, and cognitive flexibility; and their brains even began to produce new connections between neurons, which is a process typically associated with young developing brains.

The study was funded by the Deutsche Forschungsgemeinschaft, a research foundation financed by the German government as the country launches its new legalisation policy for marijuana. In addition, it also sheds some light on the mechanisms that may underlie the beneficial effects of this component of cannabis.

The science behind this finding

Ageing is often associated with a deterioration in cognitive abilities, which is thought to be the result of the deterioration of brain cells and the connections between them. Previous research studies had suggested that the endocannabinoid system (the complex network of receptors and signalling molecules in the brain and other organs) plays a crucial role in this process.

More specifically, the Type 1 cannabinoid receptor (CB1), which is abundant in the brain, seems to be related to brain aging. Previous studies have shown that the loss of CB1 activity in mice causes significant age-related deficits in learning, memory, and neuronal survival.

With this in mind, the researchers set out to explore whether improving CB1 receptor activity with low doses of THC could have the opposite effect, potentially reversing some aspects of brain aging.

They were particularly interested in how THC could affect the mTOR protein, which acts as a central regulator of cell growth, metabolism, and aging. The signalling of this protein has been linked to both cognitive performance and the aging process, making it a key target for interventions aimed at extending healthy life expectancy.

Key findings of the study

For the study, researchers used a group of young and old male mice (4 and 18 months old, with the latter being equivalent to about 65 in human years). These were randomly assigned to receive a low dose of THC or placebo over a 28-day period. THC was continuously administered via subcutaneous mini-pumps, which allowed researchers to control the dose and ensure consistent administration.

The study found that THC treatment triggered a complex cascade of metabolic changes in the brains of older mice: increased energy production, increased availability of the raw materials needed to form new brain connections, and activation of pathways associated with cell repair and renewal.

In essence, THC seemed to change the aging brains to a more youthful and energetic state, that was ready for growth and plasticity. It is as if the brains had undergone a metabolic remodelling, changing their old and slow metabolism for an agile and adolescent one.

Interestingly, these rejuvenating effects were only observed in older animals. When the same THC treatment was administered to young mice, their cognitive abilities were only slightly affected. This suggests that the effects of THC on the brain are largely dependent on age.

Researchers believe this may be due to the endocannabinoid system significantly changing with age and becoming less active in older brains. Therefore, treatment with THC in low doses can help restore it to younger performance levels.

If these findings can be transferred to humans, they could open up exciting new possibilities for the treatment of age-related cognitive impairment and perhaps even Alzheimer’s disease. A cannabis-based drug that keeps aging brains agile and flexible could certainly be revolutionary.

Of course, this doesn’t mean that older people should rush to buy or grow marijuana. The study used very precise and controlled doses of pure THC, which are quite different from those obtained by smoking a joint. Much more research is needed to determine whether these benefits would occur in humans and what the optimal treatment regime might be.

“We concluded that long-term treatment with THC initially has a cognitive enhancing effect by increasing the production of energy and synaptic proteins in the brain, followed by an anti-aging effect by decreasing the activity of mTOR and the metabolic processes in peripheral tissues”, stated Dr Andras Bilkei-Gorzo (from the UKB Institute of Molecular Psychiatry) in a press release. “Our study suggests that a dual effect on mTOR activity and metabolome could be the basis for an effective anti-aging drug and cognitive enhancer”.

The limitations of a promising research study

Although the results are promising, this study has some limitations. The research was carried out on mice and, although these animals are commonly used as models for human biology, there are significant differences between both species. It is not yet clear whether the same effects would be observed in humans, and further studies are needed to explore possible therapeutic applications of THC in ageing populations.

Additionally, the study focused on a specific dose and duration of the THC treatment, so different doses or longer treatment periods may produce different results, which could be either more beneficial or potentially harmful. Future research should explore these variables in more detail to determine the optimal treatment protocol to maximise the anti-aging effects and minimise potential risks.

An important step towards anti-aging therapies

This research is based on previous studies that demonstrated the ability of THC to reverse age-related cognitive impairment by increasing synapse density in older mice. Although the exact mechanisms remain unsolved in part, the link between mTOR signalling, metabolic processes, and brain aging offers a promising avenue for the development of treatments that challenge this aging.

Research is underway to find effective therapies for age-related cognitive impairment. And this study offers hope that THC in low doses may one day be part of a more comprehensive strategy to improve cognitive health and prolong healthy longevity in seniors.