Effects of constant light exposure on allergic and irritant contact dermatitis in mice reared under constant light conditions

Abstract

Environmental light levels can affect physiological functions, such as general activity, body temperature and metabolism. Irregular lifestyles, such as those involving exposure to light during the night, can exacerbate the clinical symptoms of several inflammatory skin diseases. However, the effects of constant light exposure on immune responses are not fully understood. This study aimed to elucidate the effects of constant light exposure on two major types of skin reactions, allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD). BALB/c mice were kept under constant light conditions or a normal light and dark cycle, and their ACD and ICD responses were assessed after the topical application of 2,4,6‐trinitro‐1‐chlorobenzene and croton oil, respectively, to the ear skin. Interestingly, in both ACD and ICD, the ear‐swelling response and local leukocyte infiltration were aggravated by constant exposure to light, which has previously been shown to severely disturb the behavioural rhythms of mice. In ACD, these findings were accompanied by increases in the numbers of degranulated mast cells and eosinophils. These results suggest that constant light exposure intensifies allergic and non‐allergic skin inflammation.

Development of Guar Gum Hydrogel Containing Sesamol-Loaded Nanocapsules Designed for Irritant Contact Dermatitis Treatment Induced by Croton Oil Application

“…In the present study, an in vivo model of the croton-oil-induced irritant contact dermatitis was performed to assess the therapeutic potential of the hydrogel containing sesamol in the free or nanoencapsulated form. Croton oil, because of its main constituent, 12-O-tetradecanoylphorbol-13-acetate (TPA), is recognized as a compound able to experimentally induce irritant contact dermatitis [ 46 ]. In the present study, the croton oil application induced skin inflammation characterized by edema formation and leukocyte migration to the injured tissue.…”

Looking beyond Self-Protection: The Eyes Instruct Systemic Immune Tolerance Early in Life

“…At this point, we would like to comment on a few other physiological processes that might contribute to explaining DSCH exacerbation in 60-day-old BE mice. The recruitment of regulatory T lymphocytes is sensitive to circadian entrainment [ 128 ] and to melatonin’s systemic and local availability [ 129 , 130 , 131 ]. Neonatal enucleation might thus condition early colonization of the skin by regulatory T cells and/or resident memory T cells [ 27 , 132 ] after shifting the availability of melatonin [ 133 ].…”

Recent progress at the psoriasis and atopic dermatitis research front: An experimental dermatology perspective

“…Many environmental factors, including light exposure, continuously challenge skin homeostasis. In their study, Mizutani et al 32 . determined how constant light exposure alters immune response.…”