Time-Restricted Feeding Shifts the Skin Circadian Clock and Alters UVB-Induced DNA Damage

Abstract

Summary: The epidermis is a highly regenerative barrier protecting organisms from environmental insults, including UV radiation, the main cause of skin cancer and skin aging. Here, we show that time-restricted feeding (RF) shifts the phase and alters the amplitude of the skin circadian clock and affects the expression of approximately 10% of the skin transcriptome. Furthermore, a large number of skin-expressed genes are acutely regulated by food intake. Although the circadian clock is required for daily rhythms in DNA synthesis in epidermal progenitor cells, RF-induced shifts in clock phase do not alter the phase of DNA synthesis. However, RF alters both diurnal sensitivity to UVB-induced DNA damage and expression of the key DNA repair gene, Xpa. Together, our findings indicate regulation of skin function by time of feeding and emphasize a link between circadian rhythm, food intake, and skin health. : Little is known about the effect of time of feeding on skin function. Wang et al. find that time-restricted feeding schedules affect skin gene expression, epidermal progenitor cell proliferation, and UVB-induced DNA damage, pointing to a modulatory role for food-intake timing in skin biology. Keywords: skin, circadian clock, time-restricted feeding, cell cycle, metabolism, DNA damage, aging