Figure 4.

Ectoine as well as antioxidants prevent ceramide generation and subsequent receptor translocation. (A) Flow cytometric analysis of intracellular ROS generation in RLE-6TN cells measured by relative intracellular DCF fluorescence after treatment with the indicated doses of CNP [μg/cm², 1 h], CP [μg/cm², 1 h], BSA-coated CNP, or C6 ceramide [5 μM, 15 min] and pre-treatment with the respective inhibitors tocopherol [Toco; 50 μM] N-acetylcysteine [NAC; 0.1 mM], or ectoine [E; 1 mM]. C indicates respective vehicle controls. (B) Amount of ceramide generation was detected by lipid extraction and HPTLC in RLE-6TN cells. (C) EGFR translocation as described in Figure 2 after treatment and pre-treatment as described above. (D) EGFR activation as described in Figure 1 after treatment and pre-treatment as described above. Means in A, C, and D are given as values relative to the respective controls. *, Significantly different from control; †, significantly different from 10 μg/cm² CNP alone; §, significantly different from C6 alone.