Peroxisome proliferator-activated receptors (PPARs) are fatty acid activated transcription factors that belong to the nuclear hormone receptor family. They are initially known as transcriptional regulators of lipid and glucose metabolism, although further evidence has also been accumulated for other functions. Due to the nature of all PPAR isotypes which are expressed and exert effects by regulating the functions of cell types residing and infiltrating in the skin, PPARs represent a major research target for the understanding and treatment of many skin diseases. Atopic dermatitis (AD) is a chronic and relapsing disease characterized by skin barrier dysfunction and immune dysregulation. Skin barrier disturbance is one of the exacerbation factors of AD, due to facile penetration of molecules such as antigens. From the aspect of immune dysregulation, innate and acquired immunity including cell proliferation, cell differentiation, and cytokine network are involved in the pathogenesis. In this review, the role of PPAR in AD and the possibility of its agonist for the treatment of AD are discussed.

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