An ex vivo model of human skin photoaging induced by UVA radiation compatible with summer exposure in Brazil

• Published in: Journal of photochemistry and photobiology. B, Biology Vol. 221; p. 112255
• Main Authors: Saguie, Bianca Oliveira, Martins, Rayssa Lopes, Fonseca, Adenilson de Souza da, Romana-Souza, Bruna, Monte-Alto-Costa, Andréa
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.08.2021; Elsevier BV
• Subjects: Aging; Aging (artificial); Carcinogenesis; Carcinogens; Collagen; Compatibility; Dermis; DNA damage; Elastin; Epidermis; ex vivo model; Explants; Exposure; Human skin; Inflammation; Ozone layer; Ozonosphere; Photoaging; Radiation damage; Skin; Ultraviolet radiation; UVA radiation; Brazil; Human skin; UVA radiation; ex vivo model; Photoaging
• ISSN: 1011-1344; 1873-2682
• DOI: 10.1016/j.jphotobiol.2021.112255

Skin is the largest body organ and can be affected by several factors, such as ultraviolet (UV) radiation. UV radiation is subdivided in UVA, UVB and UVC according to the radiation wavelength. UVC radiation does not cross the ozone layer; UVB cause DNA damage and is closely related to carcinogenesis; UVA radiation penetrates deeply into the skin, reaching epidermis and dermis and is considered the main promoter of skin aging, known as photoaging. In order to understand photoaging mechanisms and propose efficient therapies, several photoaging study models have been developed, each with benefits and limitations, but most of them use very high doses of UVA radiation, which is not compatible with our daily sun exposure. The objective of this work was to develop a human ex vivo photoaging model induced by UVA exposure compatible to a summer in Brazil. For this, human skin fragments were obtained from healthy donors who underwent otoplasty surgery and skin explants were prepared and placed in plates, with the epidermis facing upwards. Skin explants were exposed to UVA at 16 J/cm2 carried out by protocols of 2 or 4 exposures. Results showed an increase of oxidative damage, inflammatory cells, collagenolytic and elastolytic MMPs expression as well as a decrease of elastin expression, suggesting that the experimental model based on skin explants is able to evaluate UVA-induced aging in human skin. •A new model of ex vivo human skin to study UVA-induced effects.•UVA radiation compatible with summer exposure induces skin photoaging in ex vivo skin.•Realistic UVA doses induces ex vivo skin photoaging.