Jennifer Gherardini, Jeannine Wegner, Jérémy Chéret, Sushmita Ghatak, Janin Lehmann, Majid Alam, Francisco Jimenez, Wolfgang Funk, Markus Böhm, Natalia Botchkareva, Chris Ward, Ralf Paus, Marta Bertolini
OBJECTIVES: While the effect of ultraviolet radiation (UVR) on human skin has been extensively studied, very little is known on how UVR impacts on hair follicle (HF) homeostasis. Here, we investigated how solar spectrum UVR that hits the human skin surface impacts on HF biology, and whether any detrimental effects can be mitigated by a widely used cosmetic and nutraceutical ingredient, caffeine. METHODS: Human scalp skin with terminal HFs was irradiated transepidermally ex vivo using either 10 J/cm2 UVA (340-440 nm) + 20 mJ/cm2 UVB (290-320 nm) (low dose) or 50 J/cm2 UVA + 50 mJ/cm2 UVB (high dose) and organ-cultured under serum-free conditions for 1 or 3 days...
February 11, 2019: International Journal of Cosmetic Science