A comprehensive topical antioxidant inhibits oxidative stress induced by blue light exposure and cigarette smoke in human skin tissue

OBJECTIVE: Skin damage from visible light predominantly results from exposure to the blue light spectrum (400‐500 nm) which generates Reactive Oxygen Species (ROS) causing a cascade of harmful effects to skin. Topical antioxidants reduce the effects of free radical damage caused by environmental exposures. This study evaluated a comprehensive topical antioxidant's ability to inhibit ROS production induced by blue light and cigarette smoke (CS) in human skin. METHODS: Two experiments were conducted utilizing human skin (Fitzpatrick Skin Types III and V; N = 3, each). After confirmed reactivity of untreated tissues at 412 nm, 20J/cm(2), untreated and pretreated (WEL‐DS, 2 mg/cm(2)) skin tissue was exposed to blue light and blue light plus CS and left overnight. A nonfluorescent probe (DCFH‐DA) was added to skin and exposed to blue light (412 nm, 20J/cm(2)) and blue light plus CS. Fluorescent 2’,7’‐DCF was generated upon enzymatic reduction and subsequent oxidation by ROS. RESULTS: ROS increased at least tenfold following initial exposure to blue light and blue light plus CS in untreated skin. Pretreatment with WEL‐DS decreased ROS in FST III exposed to blue light by 51% and 46% in skin exposed to blue light plus CS vs. untreated skin (both, P < .001). In FST V, pretreatment with WEL‐DS decreased ROS exposed to blue light by 54% (P < .001) and 50% in skin exposed to blue light plus CS vs. untreated skin (P < .0001). CONCLUSION: WEL‐DS demonstrated significant reduction in ROS induced by blue light and blue light in combination with CS compared with untreated, exposed skin.