A Novel Look at Mechanisms and Applications of Xanthohumol (XN) in Dermatology and Cosmetology

Xanthohumol (XN), representing the group of chalcones, is a hydroxyl and superoxide free radical scavenger. It also has antimicrobial properties, showing antibacterial activity against Staphylococcus aureus, Staphylococcus pyogenes, Staphylococcus epidermidis and Propionibacterium acnes. XN exerts an inhibitory effect on tyrosinase (it hinders the oxidation of l-tyrosine and l-DOPA). However, it also affects the transport of pigment (through a reduction in the number and length of dendrites) and its degradation (through damage to melanosomes). Additionally, it has been shown to inhibit the different activation pathways of the premeditated response in macrophages and reduce the secretion of pro-inflammatory cytokines TNF-α, IL-6 and IL-1β. Xanthohumol also improves skin elasticity by reducing the activity of elastase and MMP 1, 2 and 9, and it increases the expression of type I, III and V collagen, as well as elastin and fibrillins in skin fibroblasts. It acts against the main factors contributing to the pathogenesis of acne by inhibiting pro-inflammatory mediators (e.g., COX-2, PGE2, IL-1β and TNF-α). Moreover, it shows antibacterial activity against P. acnes and S. aureus, as well as seboregulatory and antioxidant properties. It has also been recognized that XN intake could affect diabetic wound healing. XN shows antitumoral activity, e.g., in the case of skin melanoma, which is associated with the antioxidant, pro-apoptotic, anti-angiogenic and immunostimulating effects of this compound.