Administration of Protein Kinase D1 Induces a Protective Effect on Lipopolysaccharide-Induced Intestinal Inflammation in a Co-Culture Model of Intestinal Epithelial Caco-2 Cells and RAW264.7 Macrophage Cells

Figure 4

Effect of PKD1 on IL-8, TNF-α, β-catenin, and PPAR- mRNA expression in Caco-2 cells. Protein kinase D1 (PKD1; 0.001, 0.1, 10, 100 ng/ml) was administered apically to Caco-2 cells in co-culture with RAW264.7 cells. An inflammatory response was induced in RAW264.7 cells with 1 μg/ml lipopolysaccharide (LPS, E. coli: O127). Effects of PKD1 on IL-8, TNF-α, β-catenin, and PPAR- expression levels were evaluated in two different situations: (■) LPS was administered to RAW264.7 cells for 3 h, followed by PKD1 to Caco-2 cells for 3 h to investigate whether PKD1 can ameliorate an already established inflammation. (□) PKD1 was administered to Caco-2 cells for 3 h at which point RAW264.7 cells were stimulated with LPS for 6 h to evaluate whether PKD1 can suppress inflammation initiation. Data are presented as mean transcriptional levels relative to the negative control (0% FCS, unstimulated) with 95% confidence intervals (). Significant differences () within concentrations of PKD1 and LPS are indicated by the uppercase letters.

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