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J. Cosmet. Sci., 71, 425–437 (November/December 2020) 425 Soothing Effect of Pogostemon cablin Extract (Patchouli), via Cannabinoid Receptor 2 Modulation in Human Skin FLORIAN LABARRADE, ARMELLE PERRIN, YOLENE FERREIRA, GILLES OBERTO, CATHERINE GONDRAN, CORINNE MOREL, and KARINE CUCUMEL , Ashland Specialties France, Global Skin Research Center, Nice 06904, France (F.L., A.P., Y.F., G.O., C.G., C.M., K.C.) Accepted for publication August 6, 2020 . Synopsis Skin functions as a neuro-immuno-endocrine tissue with well-defi ned neuronal networks and functions. The endocannabinoid system has been proven to be an important, homeostatic regulator for homeostatic and infl ammatory events. The system comprises endogenous or exogenous ligands and receptors (CB1 and CB2). In the present study, we evaluated the soothing properties of a Pogostemon cablin (patchouli) extract. Agonist AM1241 and antagonist AM630 were used for CB2 receptor activation/inhibition. Expression of CB2 receptor and β-endorphin was monitored by immunohistochemistry. Skin infl ammation was induced with ultraviolet B (UVB) or lipopolysaccharide (LPS), and the following markers were used to highlight the anti- infl ammatory properties of the extract: transient receptor potential vanilloid 1 (TRPV1), interleukin receptors 1 (IL1R1), and the interleukin 6 signal transducer (IL6ST). Our results demonstrated the implication of the CB2 receptor in the skin infl ammation process. The expression of CB2 receptor and β-endorphin was increased 48 hours after application of the extract. Furthermore, patchouli extract application helped to reduce IL1R1, IL6ST, and TRPV1 expression, in skin exposed to UVB or LPS. In conclusion, the application of the patchouli extract helps maintain skin integrity and reduce skin discomfort via modulation of CB2 receptor stimulation and the subsequent β-endorphin release. IN T RODUCTION Sk in serves as the fi rst protective barrier between the body and the environment, with both passive and active roles against chemical, physical, and microbial insults (1). Human skin produces numerous neuropeptides that play a role in various cutaneous functions and diseases, acting as neuromodulators, neurotransmitters, and hormones. Many different biologic actions of neuropeptides in skin have been demonstrated, such as infl ammatory, proliferative, and reparative processes after injury (2). Cannabinoids represent a broad class of chemical compounds derived from the cannabis plant. Cannabinoids are chemical Address all correspondence to Florian Labarrade at fl abarrade@ashland.com.