Cannabinol

Cannabinol (CBN), a cannabinoid with the molecular formula C21H26O2, was the first cannabinoid to be identified and isolated from cannabis in 1899, belongs to the phytocannabinoids, less well known than CBD, but is also sold in combination with CBD. Cannabinol is the non-enzymatic oxidation by-product of tetrahydrocannabinol, but is only found in small amounts in Cannabis indica . When cannabis is exposed to air or ultraviolet light (e.g. sunlight) over a longer period of time, THCA converts to cannabinolic acid (CBNA). CBN is then formed by decarboxylation of CBNA. Degraded or oxidized cannabis products such as traditionally produced hashish contain CBN in relevant concentrations.

CBN oils are used in the cosmetics industry.

Cannabinoids are a collective group of compounds that act on cannabinoid receptors. They include plant phytocannabinoids, synthetic cannabinoids and endogenously formed endocannabinoids. Cannabinol binds as a partial agonist, preferentially to the cannabinoid G protein-coupled receptor CB2, which is expressed mainly on a variety of immune cells, such as T cells, B cells, macrophages and dendritic cells, but also on keratinocytes (Wilkinson JDet al. 2007). Stimulation of CB2 receptors by cannabinol can both induce apoptosis in these cells and inhibit the production of a variety of cytokines. Cannabinol binds only weakly to CB1 receptors. The substance exerts a weak psychotropic effect (Sheriff Tet al. 2020).

In animal and human studies, CBN was shown to have sedative and anticonvulsant effects. The substance has significant immunosuppressive, anti-inflammatory and antimicrobial effects. Cannabinoid (CB) receptors are present in human skin. Anandamide, an endogenous CB receptor ligand, inhibits epidermal keratinocyte differentiation. CBN inhibits the activity of a number of enzymes, including cyclooxygenase, lipoxygenase, and a number of cytochrome P450 (CYP) enzymes (e.g., CYP1A1, CYP1A2, CYP2B6, CYP2C9, CYP3A4, CYP3A5, CYP2A6, CYP2D6, CYP1B1, and CYP3A7). Furthermore, CBN may stimulate the activity of phospholipases.

CBN has the potential to be effective in topical applications. When applied topically, CBN is absorbed to a relevant extent (Stinchcomb AL et al 2004).

Inhibition of keratinocyte proliferation: The plant cannabinoids delta-9-tetrahydrocannabinol, cannabidiol, cannabinol, and cannabigerol inhibit the proliferation of a hyperproliferating human keratinocyte cell line in a concentration-dependent manner (Wilkinson J et al 2007).

CBN stimulates the recruitment of quiescent mesenchymal stem cells in bone marrow and promotes bone formation.

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6. Wilkinson JDet al. (2007) Cannabinoids inhibit human keratinocyte proliferation through a non-CB1/CB2 mechanism and have a potential therapeutic value in the treatment of psoriasis. J Dermatol Sci 45:87-92.
7. https://evsexplore.semantics.cancer.gov/evsexplore/concept/ncit/C84510