Sphinganine inhibits macrophage polarization and protects against sepsis-induced intestinal injury

Figure 3 Sphinganine inhibits macrophage polarization and alleviates intestinal injury via toll like receptor 2. A-D: Enzyme-linked immunosorbent assay results showed that sphinganine reduced serum levels of diamine oxidase (A), diamine oxidase (IL)-1β (B), tumor necrosis factor-α (C), and IL-6 (D), which were reversed by treatment with the toll like receptor (TLR) 2 agonist fibroblast-stimulating lipopeptide-1 (FSL-1); E and F: Hematoxylin and eosin staining demonstrated that FSL-1-mediated activation of TLR2 aggravated sepsis-related intestinal damage, while sphinganine treatment protected against such injury; G: Immunofluorescent staining showed that FSL-1 treatment decreased zonula occludens-1 expression in colon tissues, and sphinganine counteracted this effect; H and I: Immunofluorescence analysis of macrophage polarization markers. The beneficial effects of sphinganine on cluster of differentiation (CD) 86 and CD206 expression were reversed by FSL-1 treatment. Data are presented as mean ± SEM. ^aP < 0.05. ^bP < 0.01. ^cP < 0.001. DAO: Diamine oxidase; IL: Interleukin; TNF: Tumor necrosis factor; CLP: Cecal ligation and puncture; FSL-1: Fibroblast-stimulating lipopeptide-1; ZO-1: Zonula occludens-1; CD: Cluster of differentiation; DAPI: 4’,6-diamidino-2-phenylindole.