There is a growing body of evidence to suggest that the endocannaboid system has a fundamental role to play in various aspects of the aging process, both mental and somatic. Furthermore, regular use of cannabis itself may assist in slowing down this process, although the precise mechanism of action has not been ascertained.
Brain ageing & the endocannabinoid system
The ageing of the brain, and the resultant neurodegeneration associated with it, cause increasing levels of debilitation and cognitive decline as they progress. Common features of typical age-related neurodegeneration include memory loss, difficulty with orientation, and difficulty paying attention (although research suggests that the latter may be more closely related to impairment of hearing and vision rather than directly due to cognitive decline).
Abnormal brain ageing is also a significant concern to health authorities worldwide-increasingly so, as the global population ages and age-related health problems become more prevalent. Conditions that cause the brain to age or decline prematurely or too rapidly include Alzheimer’s, Parkinson’s, Huntington’s, and amyotrophic lateral sclerosis (ALS).
There have been various studies into the potential for cannabis and cannabinoid therapies to slow or even reverse the symptoms of neurodegeneration in diseases such as Alzheimer’s, as well as a significant amount of research into the possibility that normal brain ageing could be slowed by cannabis use.
Research into normal brain ageing and cannabis
The ageing process is determined by the balance between detrimental and defensive biological processes, such as oxidative stress and antioxidation; the bulk of research suggests that the endocannabinoid system (ECS) is more closely associated with the latter camp than the former.
In terms of general, non-pathological ageing, it has been demonstrated that on a molecular level, cannabinoids regulate mitochondrial activity, act as antioxidants (via a mechanism that appears to be independent of the principal cannabinoid receptors), and modulate processes that remove harmful macromolecules from brain and CNS tissue.
On a cellular level, the ECS regulates expression of the important neurotransmitter, brain-derived neurotrophic factor (for example, chronic exposure to THC induces upregulation of BDNF in rats), an important protein responsible for the development and maintenance of healthy neurons, which underlies its ability to assist in neurogenesis (growth of new neurons).
Pathological brain ageing and the ECS
In terms of ageing that is non-typical or pathological (i.e. that caused by disease), the ECS has been widely implicated in the suppression of neuroinflammation (for example, mice bred to lack CB1-receptors exhibit significantly higher levels of neuroinflammation), which can lead to the development of neurodegenerative diseases and early-onset age-related cognitive decline.
Thus, it is clear that the ECS (particularly with regards to the CB1-receptors and their agonists) has a vital role in the onset and progression of the ageing process. The two best-known endogenous cannabinoids, anandamide and 2-AG, are both agonists of the CB1-receptor; it is not known with certainty which of the two is more deeply involved in the anti-ageing process.
However, preliminary research indicates that low levels of fatty acid amide hydrolase (FAAH; the enzyme responsible for the degradation of anandamide) are associated with delayed brain ageing, suggesting that high levels of anandamide are likely to have a beneficial effect. Thus, FAAH inhibitors would make an ideal candidate for further research.
Ageing of skin & the endocannabinoid system
The other major aspect of ageing aside from the mental is obviously the physical, and this aspect is primarily characterized by changes to the epidermis, dermis and hypodermis (the layer of fat, fibroblasts, and macrophage cells that lies just beneath the dermis).
Exposure to UVA and UVB rays causes thinning of the dermal layer, meaning that as skin ages, it becomes less elastic and begins to sag, causing the epidermis to droop and become wrinkled. The skin also becomes prone to blemishes such as liver spots, which are thought to arise due to an accumulation of aged basal cells that can no longer be removed by the body’s natural waste-clearing mechanisms.
It is now known that the endocannabinoid system is involved in the maintenance of healthy skin in various ways, and that dysfunction of the ECS could be behind various neurodegenerative diseases. A 2012 study published in the journal Neurobiology of Aging observed that in mice bred to lack CB1-receptors, not only did the subject animals exhibit early onset of neurodegeneration, they also demonstrated histological changes in skin elasticity resembling those found in typical ageing. However, the researchers noted that no other signs of ageing were seen to be associated with the deletion of the CB1-receptors.
Furthermore, a 2010 study demonstrated that anandamide was integral to the processes of basal cell proliferation and death. Basal cells are the primary constituent of the epidermis, making up approximately 90% of all cells present, and it is well-known that maintenance of healthy skin requires their effective proliferation, growth and eventual death.
Senescence, cell death & the endocannabinoid system
The process of programmed cell death is involved in the process of ageing in various key ways, and there is a growing body of evidence suggesting that the ECS has an integral role to play.
While there have been no studies specifically investigating the role of the ECS in cell death related to the normal ageing process, there are abundant studies documenting the ability of both CBD and THC to cause it in general terms.
For example, it has been shown that that leukaemia and glioma (a tumour of the glial tissue of the brain) cells are sensitive to cannabidiol-induced apoptosis(apoptosis is a primary form of programmed cell death), but that primary monocytes and glial cells are relatively insensitive. THC has been shown to induce apoptosis in human prostate cancer cells, although it is thought that this effect may be mediated by some other means that via the cannabinoid receptors, as other agonists such as WIN55,212-2 had no effect.
A 2008 study also showed that the cannabinoid acid and precursor to THC, THCA, is responsible for the regulation of cell death in the leaves of cannabis plants. The study showed that THCA is injected into leaf tissues, where it causes mitochondrial dysfunction within leaf tissues, and ultimately leads to necrosis (another important type of cell death).
Other ways that cannabis & hemp can help
As well as anandamide, THC, and CBD, there are other phyto- and endocannabinoids that may have a role to play in the maintenance of healthy skin. For example, the endogenous CB2-receptor agonist n-palmitoylethanolamine has been shown to reduce pruritus (itching of the skin) reported in patients with atopic dermatitis and related diseases; although pruritus can affect individuals of any age, its occurrence becomes far more prevalent with age.
Furthemore, the unique combination of omega-3 and omega-6 oils found in hemp seed may also have distinct benefits on the process of skin ageing. A 2012 study on mice concluded that the sample group administered with hemp oil demonstrated significant improvements in dermal thickness, along with improved collagen fibre texture, and increased numbers of hair follicles (reduction in hair follicle count leading to balding is another common sign of ageing).
Could cannabis sometimes speed the rate of ageing?
Although it seems that cannabis use is generally advantageous in terms of delaying the ageing process, there may be certain circumstances in which it can have a deleterious effect.
Smoking as a delivery method may negate the potential benefits of cannabinoids as an anti-ageing treatment, and may even contribute to accelerated skin ageing. This is due to the fact that cannabis smoke contains many of the same hydrocarbons as tobacco smoke.
Despite evidence suggesting that these hydrocarbons (although considered to be pro-carcinogenic) are not associated with cancer in cannabis smokers, there is evidence to suggest that they do nonetheless cause damage on a cellular level, in ways that may be dependent on genetic makeup.
Overall, it appears that the likelihood of cannabis use speeding the process of ageing is small, and that regular use (although preferably via a means other than smoking) could in fact slow or even reverse clinical signs of ageing seen in the brain and the tissues of the epidermis and dermis.
Author: Seshata @ Sensiseeds