266 Evaluation of an extract of Pogostemon cablin (patchouli) on the cannabinoid receptor CB2 and associated reduction of skin discomfort sensation

Abstract

The skin has its own cannabinoid system which is part of its neuro-endocrine system. This system participates in various functions such as proliferation, differentiation, inflammation as well as the control of pain and itch sensation. Whereas CB1 is predominantly expressed in the central nervous system and peripheral tissues, CB2 was found mainly in non-neuronal tissues. The effects on CB2 have been previously reported as a potential target for reducing the sensation of skin discomfort, without psycho-active effects. In particular, CB2 receptor stimulation leads to beta-endorphin release from keratinocytes, that exhibits anti-nociceptive effects. Furthermore, cannabinoids can interact with other receptors associated with itch sensation and sensitive skin such as TRPV1. The present study aims to evaluate the effect of an extract of Pogostemon cablin (patchouli) on CB2 expression on ex vivo skin biopsies. This extract is obtained by a supercritical CO2 extraction of patchouli leaves and contains volatile molecules, including phytocannabinoids, as well as flavonoids, phytosterols and fatty acids. The effects on IL1-R1 (IL1 receptor) and TRPV1 were also investigated on ex vivo skin biopsies exposed to UVB irradiation or bacterial lipopolysaccharide (LPS), after application of a formula containing the patchouli extract. The level of CB2 expression in skin biopsies was observed to have increased after application of the extract. In skin biopsies with an increased inflammatory level, induced either by UVB or LPS, the application of the extract was associated with a reduction of the level of IL1-R1 and TRPV1. The ECS is one of the system the skin uses to respond to diverse stressors that lead to unpleasant skin sensation. The increase in CB2 expression, and the reduction of the inflammatory level and of TRPV1 associated with sensitive skin sensation are in favor of a decrease in the perceivable signs of skin discomfort.