Activation of Protease-Activated Receptor 2-Mediated Signaling by Mast Cell Tryptase Modulates Cytokine Production in Primary Cultured Astrocytes
Figure 5
Effects of tryptase (Tt) on the activation of MAPKs and PI3K/AKT. (a) Time courses of tryptase activated p38, JNK, ERK, and AKT, which was assessed by increased phosphorylation of tyrosine residues of these kinases. Astrocytes were incubated with 1 μg/mL of tryptase for the indicated periods (0, 15, 30, 60, 120, and 240 min). (b) FSLLRY-NH2 (FS, 200 or 400 μM) alleviated tryptase (1 μg/mL) induced MAPKs and PI3K/AKT activation. Astrocytes were incubated with 1 μg/mL of tryptase in the presence or absence of FS, an antagonist of tryptase at 37°C for 30 min. Activated p38 (p-p38), JNK/SAPK (p-JNK), ERK (p-ERK), and AKT (p-AKT) species were detected by immunoblot analysis with antibodies specific for the phosphorylated forms of each kinase. The amount of protein loaded in each lane was confirmed by measuring the amount of p38, JNK, ERK, and AKT reacted to the antibody against the unphosphorylated form of each kinase. This is a representative experiment independently performed three times. , versus control groups (Con), versus corresponding tryptase treatment groups.
