Insulin-Like Growth Factor-1 Increases the Expression of Inflammatory Biomarkers and Sebum Production in Cultured Sebocytes

Background: Acne vulgaris has been linked to the Western diet.Hyperglycemic diet increases insulin and insulin-like growth factor (IGF)-1.Deeper insights into IGF-1-mediated signal pathway are critical importance to understand the impact of Western diet.Objective: We investigated the effect of IGF-1 on the expression of inflammatory biomarkers and sebum production in cultured sebocytes.Methods: Polymerase chain reaction and enzyme-linked immunosorbent assay were performed to measure changes in the expression of inflammatory biomarkers including interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF)-α, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), IGF1R, IGFBP2, sterol response element-binding protein (SREBP), and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PI3KCA) after the treatment of cultured sebocytes with 10 -7 M or 10 -5 M IGF-1.Sebum production was evaluated after the treatment of cultured sebocytes with 10 -7 M or 10 -5 M IGF-1 using lipid analysis.Results: The expression levels of IL-1β, IL-6, IL-8, and TNF-α in cultured sebocytes after treatment with 10 -7 M or 10 -5 M IGF-1 were increased.Increased gene expression levels of NF-κB in cultured sebocytes were also shown after 10 -7 M or 10 -5 M IGF-1 treatments.Gene expression of these inflammatory biomarkers was decreased after 10 -7 M or 10 -5 M IGF-1 treatment in the presence of 100 nM NF-κB inhibitor.Treatment with 10 -7 M or 10 -5 M IGF-1 increased the gene expression levels of IGF1R, IGFBP2, SREBP and PI3KCA in cultured sebocytes.Sebum production from cultured sebocytes treated with 10 -7 M or 10 -5 M IGF-1 was also increased.Conclusion: It is suggestive that IGF-1 might be involved in the pathogenesis of acne by increasing both expression of inflammatory biomarkers and also sebum production in sebocytes.(Ann Dermatol 29(1) 20∼25, 2017)