Research advancements in the immunomodulating effect of sphingosine-1-phosphate in skin diseases

Sphingosine-1-phosphate (S1P) is a bioactive lipid metabolite that acts as an extracellular and intracellular messenger in a variety of biological activities, many of which are mediated by binding to S1P-specific G protein-coupled receptors. S1P receptors can affect cell fate by mediating cell differentiation, proliferation, and apoptosis. S1P mainly plays an immunomodulatory role in vivo. In recent years, increasing numbers of studies have shown that S1P is involved in the occurrence and development of immune-related skin diseases by regulating keratinocyte differentiation, proliferation, and apoptosis; lymphocyte migration; and angiogenesis. This review explores the metabolism and signal transduction mechanism of S1P, focusing on research advancements in the immune regulation function of S1P and its impact on immune-related skin diseases. The aim is to provide insights that can contribute to the research and application of S1P in immune-related skin diseases.